total loss of e-mail history related to the Apple e-mail client or the iOS e-mail app

Hardware: iPhone 6s

Software: gmail desktop and mobile, inbox by gmail, apple mail

Problem description: over the past three weeks my entire gmail inbox messages have been moved to my trash folder without notifying me. I have checked my settings under gmail and nothing indicates that I have changed something. Please help. Thank.

Below is the answer that I got on gmail help forum:

Question: Is there a way to make sure this doesn't happen in the future

Answer from gmail help forum: "The current best suggestion is to NOT use the iOS e-mail app, but download the Gmail app instead. Some people have said they like the Outlook app.".