FRUSTRATED! Getting prompted to change password every day or two.

For some reason, when I go to play on my PS4 it forces me to change my password before I can log back in .  All of a sudden this is happening every day or two, and it's incredibly frustrating to have to go to my PC, check my email for a message from PSN, change the password, etc.

Is there a reason why I would keep getting forced to change my password?  Is there anything that I can do to stop this?

Thanks!

T