I had two of those phones on tmobile network.....had those same problems and then some it started using my battery, data, and I could not open or download any apps. I did 5 resets and every combination even took out my. SD card and had no apps and it still did it. So finally I contacted ZTE and after talking to a ton of people I was told there is no fix and there is no plans to fix. So I talked and talked to T-Mobile they wanted to send me another ZTE which would do the same thing so finally I saw mobile CEO on FB and sent a message asking for help within a couple of hours I was talking to an executive and they swnt me two new LG V30 plus I offered to pay any difference from the value of what. Paid for my ZTE.....hope this helps you.