ATT.NET

I've had browser issues the past couple days ( Win10 Edge ) but... seems they began with Microsoft recent security updates. My wifi, phone, etc.., still work fine so I can't fault AT&T for my pc internet browser issues. No cable here so I have to settle for AT&T.
I just 10 minutes ago closed Edge and opened ie11. It seems to be working better ( time will tell ).
AT&T uses yahoo mail so you could try to log in at yahoo mail. Same user name and password or try a different browser.