Wifi not reconnecting...

I am not sure but ever since the new update my system did, the wifi network never recconects to it anymre, and when I do, it disconnects from the network within a few hours, has anyone had this issue?

things I have done:

Rebooted wifi router countless of times

System is about 4-6 feet from main router and about 3 feet from wifi system extender

Not to many things are connected to the wifi system

All of this weird connectivity issues began after the update, never had an issue before then.