Difficulty with logging in and transferring my data to a new phone

Hello there!

I recently upgraded my phone (Galaxy A52s to Galaxy A56) and tried logging in with my new phone and transferring data from the old one. For some reason, the app keeps logging me out on both phones and on the new one it reverts to an earlier save of my chat history. The new phone is a dual SIM phone and the old SIM card is in the secondary slot there but I use the primary card for everything.

Does this sound familiar to anybody? I appreciate all input