2 cellular plans -fb messenger not working

Hello.

I have 2 cellular plans on my iPhone 13. Unfortunately I can’t talk or have video calls via fb messenger or WhatsApp - I can’t even connect with other people and if I do I experience horrible problems. This doesn’t happen when I’m using wifi. My sim operator is the same on both cards. If I switch one plan off it works fine. It happens only in iPhone - there’s no problem with using my two SIM cards on an android phone. What do I do?