Nexus 5X can't connect to internet over cell connection; X on signal strength indicator I have a Nexus 5X, which I've had for 2 years and used without any serious problems until today. It is now running Android 8.1. I have Ting as my carrier.

I'm having a strange issue. Most of the time, I see an X over the signal strength indicator, and if I try to connect to the internet, it takes a long time and then tell me the site can't be reached (see the first screenshot).

Here is the strange part: if I connect to a WiFi connection, everything works fine and the X goes away (see the second screenshot). If I disable WiFi, the X comes back and I can't connect. I can't stay connected to WiFi everywhere I go all the time, so I'd like to fix this problem.

I tried googling for problems like this and tried everything that was suggested: I restarted my phone multiple times, I removed and reinserted my SIM card, and yes I'm sure I have mobile data enabled.

Does anyone know why this is happening or how to get my internet connection working like before?
I figured out what was causing the problem. I had been using my phone as a hotspot, and it used an unusual amount of data, causing Ting to cut off my connection. I called their support number (1-855-846-4389) and talked to someone, and they re-enabled it.