why is my phone making me reset my apple id password every day

My apple ID will ask me to add my password for Apple ID almost every other day. It says the password I have written is wrong and will request me to reenter it. It then doesn't work so forces me to reset my password every day or every few days. It is very annoying and I will usually wait to reset it until I need to. The box will continuously pop up and ask me to enter my password and not accept the one I've changed it to after a day. What can I do to fix this? I am getting very frustrated resetting my password every few days or getting the continuous pop-up to add my password. Please help.