Android 4.4.2 not automatically connecting to wifi

I have a samsung galaxy tab 3 8.0 running android 4.4.2 unrooted. My tablet is not automatically connecting to wifi networks. It was previously automatically connecting to two wifi networks (both are home networks secured with a password) but now I have to re-enter the password every time I try to connect to either of these networks. How can I get my tablet to remember the wifi networks?