Can you help me figure out what's wrong with my cordless home phones?

My cordless phones, for the past few days, ring but I can’t hear anything from them. When they ring, I can “answer” them (stop the ringing by pressing the button) but not hear the caller and the caller can’t hear me. The caller ID does not work on them either. Their screens will indicate “incoming call” but no caller ID. The wall phone (corded) works fine.

I pushed in all the wires on the cordless phones to make sure everything is plugged in correctly, and it seems to be. Just the fact that they ring seems to indicate that they’re plugged in properly.

Can you please help me figure out what may be the issue?