Wi-Fi is a great way to make sure you're not burning through data. And hey, a lot of us use most of our data on Facebook, Instagram, and Google so I read your concerns loud and clear.
Given that you don't have any connection issues when utilizing a different Wi-Fi network or our own Verizon Wireless network, this would be something with your AT&T DSL account that you may wish to correct. I would recommend getting in touch with their team directly so you can see what may be causing the failure. Another thing you may wish to try before doing that is simply forgetting that Wi-Fi connection at home and then re-establishing it http://vz.to/Z0ixZ6 . I hope this helps!
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