jakbest Welcome to the community!
On the system side, everything is active as it should be, so you can use the bridge mode.
Our analysis:
At the moment two devices get a public IP.
Please try the following:
1. switch off your modem
2. remove all LAN cables from the Sunrise modem (Lan1-4)
3. connect a LAN cable e.g. from LAN 1 of the Sunrise modem to your router WAN port
4. switch on the Sunrise modem and wait until it is online
5. switch on your own router
6. connect all other devices to your router, nothing to the Sunrise modem.
7. test it again
Greetings
Daniele