Fairphone 4: incoming SMS not working with prepaid eSIM

Roabembauck13

Hi everyone,
I have a Fairphone 4 with a prepaid eSIM. I am experiencing a problem where I cannot receive any normal SMS messages.
The issue is:
Mobile data works correctly (LTE).Phone calls work normally.RCS messages work.Incoming SMS are never received.The sender does not get any error message; the SMS seems to be delivered normally from their side.Before the problem started, SMS reception was working correctly.
Things I already tried:
Checked APN settings (including IMS APN).Tested different network modes (LTE only / NR-LTE).Reset network settings.Cleared the SMS app cache.Checked the Android testing menu (##4636##), but I cannot find IMS registration status.
At this point I suspect either:
a Sunrise eSIM/provisioning issue,a modem/baseband configuration issue,or a Fairphone 4 telephony issue.
Has anyone experienced similar behaviour with Fairphone 4 + Sunrise eSIM?Any ideas for further troubleshooting would be appreciated.
Thanks!

Roabembauck13

Update / correction:

I need to correct my previous post: the issue is not limited to SMS.

I have now noticed that incoming and outgoing voice calls are also not working:

Incoming calls do not arrive.
Outgoing calls fail.
Incoming SMS are not received.
LTE data still works.
RCS still works.

So the problem seems to be related to voice/SMS network registration rather than only SMS reception.

Sorry for the incomplete information in my first post.

Cosmo24

Welcome to the community, Roabembauck13

We are a customer-to-customer forum, so we cannot check your account in the system.

Since data and RCS work but calls and SMS fail, maybe your network registration for voice services is blocked. Could it be that your ID verification is incomplete or expired? Please check your MySunrise portal to see if the ID check is missing. If your verification is fine, please contact the hotline at (0800 707 707) to have it checked.

Cheerio cosmo

Roabembauck13

Thanks for the suggestion.

I checked my MySunrise portal, but I could not find any information about ID verification or a missing verification status.

Roabembauck13

Additional diagnostic information:

In the Android testing menu (##4636##) I found:

Voice service: In service
Voice network type: LTE
Voice call status: inactive

This seems to indicate that the phone is connected to LTE, but voice service is not active.

Daniele_Sunrise

Roabembauck13 Could you please check whether you have VoLTE enabled or disabled, and either enable or disable it?

Here are the instructions Enabling VoLTE:

Open Settings on your phone.
Tap Network & internet.
Select SIMs and choose your mobile network operator.
Ensure Preferred Network Type is set to allow 4G/LTE.
Find and turn on the 4G Calling or VoLTE switch.

Does it work after that? You may need to restart your phone.

Greetings
Daniele

Roabembauck13

VoLTe disabled after reading other forums, didn’t change

Daniele_Sunrise

Roabembauck13 A SIM card replacement has now been initiated. Since you can’t log in to My Sunrise, you’ll need to call our support team so they can activate the new SIM card. Please try again afterward.

Greetings
Daniele

Roabembauck13

hanks for your help.

Just to clarify, I do have access to My Sunrise. I use another phone to receive the SMS for two-factor authentication.

Before reading your reply, I had already ordered a replacement eSIM myself. However, since yesterday evening, the My Sunrise portal has been showing the following status:

“Der Prozess zum Sperren/Entsperren ist in Bearbeitung.”

The process appears to be stuck, and I have not yet received a new QR code or any further update.

Could you please check whether the replacement process is still pending or if something needs to be reset on your side?

Thank you!

Daniele_Sunrise

Roabembauck13 I can’t find your customer information anymore. Please send us your customer number, address, and date of birth via private message. We’ll be happy to check the order status.

Greetings
Daniele

Roabembauck13

Update: Partial workaround after contacting Sunrise support

I spent more than an hour on the phone with a Sunrise support agent. We reset the eSIM and tried several different settings and troubleshooting steps.

We eventually found a partial workaround, although the issue is unfortunately not completely solved.

First of all, VoLTE needs to be disabled.

After every phone restart — and also whenever I notice that SMS are no longer being received — I have to do the following:

Open the Phone app.
Dial *#*#4636#*#*.
Open Phone information.
Find Set preferred network type.
Change it from NR/LTE to LTE only.
Wait a couple of minutes.
Change it back to NR/LTE.

Doing the opposite (LTE only → NR/LTE) also seems to trigger it.

fairphonefriend

@Roabembauck13 thanks so much for posting.
I have the very same problem with my Fairphone 4 / Android 15 since Monday afternoon. Several rounds with Sunrise support were non-conclusive.

The workaround is at least a start, after switching to LTE only, it works for me it seems.

@Daniele_Sunrise could you give us some context about these settings so that we can dig a bit more to solve the issue more permanently?

fairphonefriend

Update: I restarted because I wanted to try bringing back my second physical SIM that support had me remove.
Then out of curiosity I changed the setting back to VoLTE + preferred network type “5G/4G/3G/2G” on the Sunrise esim settings. Interestingly enough, despite being back to the original settings, for the moment things continue to work normally.

So far, the potential culprit is switching the preferred network type to/from LTE only. I can’t rule out that the original problem started happening after I switched to 5G (in some regions I only use 4G/3G/2G).

Roabembauck13

@fairphonefriend I’m glad to hear it’s working for you now!

Unfortunately, my experience is a bit different. After every reboot I still have to trigger the network to re-register, otherwise calls and incoming SMS don’t work.

Also, with VoLTE enabled, it never works for me.

What currently works quite reliably is:

Keep VoLTE disabled.
After every reboot, go to the preferred network type and toggle between 5G/4G/3G/2G and 4G/3G/2G (or vice versa).
After waiting a minute or two, calls and incoming SMS start working again.

So for me, it’s not just switching to LTE only once. I have to repeat this procedure after every restart, and sometimes again if incoming SMS stop arriving.

This makes me think the toggle forces the phone to re-register on the network, but there is still an underlying issue that hasn’t been fixed.

Roabembauck13

Has anyone with Sunrise (especially using an eSIM) on a Fairphone 4 found a permanent solution?

I’m also wondering whether this could be related to IMS provisioning or a modem/radio issue.

@Daniele_Sunrise Any ideas or additional debugging steps would be greatly appreciated.

Cosmo24

Roabembauck13

Daniele_Sunrise is out of office until August 17th. Since the workaround only helps until the next reboot, there might be a glitch with your eSIM profile or the VoLTE activation in the backend.

Your best option right now is to call the hotline (0800 707 707) to clarify this and have it forwarded accordingly if necessary.

fairphonefriend

@Cosmo24 thanks for the absence info, could you explain a little more what your suspicion is regarding the backend?

I think it would help others very much if we could find out what exactly to ask from support.
I called support multiple times before I found the workaround in this thread. They said they did everything they could on their end and they gave up telling me to go to a store.

Luckily, then I found this thread and my esim now continues to work.
@Roabembauck13 one thing comes to mind that might be different on how I did the workaround: I had taken the other physical sim out and only added it back in after I had the esim working again. I know it’s a bit desperate 😃 to keep retrying but just thought it would be worth mentioning.

Roabembauck13

Thanks @fairphonefriend for mentioning that. In my case I only have a Sunrise eSIM, so unfortunately I can’t try the same approach with a physical SIM.

fairphonefriend

Not sure if there are any new hints on fixing this permanently?

only noticed that it broke again after restarting the phone couple of days back, switching to/from 5G + VoLTE off helped. now if it keeps breaking, then I’m back in the same instable boat 😢

yolina123

I would like to add another Fairphone 4 case, as I seem to be experiencing a very similar issue.

I am using a physical yallo SIM (Sunrise network), not an eSIM, on a Fairphone 4 running Android 15 / FP4.QREL.15.19.2. The SMS service stopped working on 28 July 2026. In my case, voice calls and mobile data continued to work normally, but I could neither send nor receive SMS, including OTP/service SMS.

yallo has already replaced my physical SIM with a new physical SIM, but this did not resolve the issue. I also tested another SMS app instead of Google Messages, without any effect.

The workaround described in this thread does, however, seem to affect the problem:

Initially, with NR/LTE/GSM/WCDMA, SMS were not working.
I changed the preferred network type via *#*#4636#*#* to GSM/WCDMA/LTE (PRL).
Immediately afterwards, I could send and receive normal SMS and receive OTP/service SMS again.
After changing the network type again, SMS stopped working once more.
Toggling the preferred network type again then restored SMS functionality, including while NR/5G was enabled.

So in my case it does not seem to be simply “5G enabled = SMS not working”. Rather, changing the preferred network type appears to trigger a network re-registration that can restore the SMS service, very similar to what others have described here.

Since this also occurs with a physical SIM, and persisted after replacement with a new physical SIM, the issue does not appear to be limited to Sunrise eSIM profiles.

I have also reported this to Fairphone, as this increasingly looks like an interoperability or registration issue between the Fairphone 4 / Android 15 and the Sunrise network.

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