u/Several_Meringue6525

My family switched from Cox Wifi to T-Internet about 2 months ago due to T-Mobile's being cheaper. It worked well for the most part, but about 2 weeks ago, my phone started struggling to connect to the internet. This ranges from errors such as "wrong password", "connected without internet" or "internet not available." I can maybe get it to connect for an hour or two every 6 hours before it stops letting me connect again. It's been driving me mad since, and it's began to affect my mother's phone too. This drives her crazy, since she needs internet to do work. (There's usually around 7 devices connected to the internet, including my mom and myself.)

Anyone have any ideas on what to do?