wifi wont stay connected. help?

I just bought the galaxy core prime from metropcs. I have wifi in my home that all other devices connect to with no problem. I typed in the wifi password and hit connect. It connects but then quickly disconnects over and over again. I have tried downloading wifi fixers and the 0011 turn off powersaving mode and nothing seems to work. Pleaseeee help????!!!! I depend majorly on wifi since I've also noticed my 4g is slow too. :(