Help -- emails being moved or deleted Outlook 2016

Help....

When I look at an email on my PC using Outlook 2016 it automatically either removes or marks read the same email on my iphone or tablet. I have my email in outlook set as IMAP same on my iphone. I'm using Gmail linked to my PC and iphone. This was working a week ago and my pc crashed and after getting running again now I have this. I have researched, looked at every setting, etc.. I'm missing something please help me this is frustrating. Running os17 on my iphone and current window operating system.

Thanks for any help!

Kurt