Couple of thoughts. First, have you called the 1800 number for Wells Fargo to verify that it was indeed Wells Fargo calling you? Second, I had an unauthorized charge on one of my credit cards several years ago, and it was one I never use, and in fact, had never been activated. The bank was very secretive about it, but restored my money immediately. I suspect that it was an inside job by an employee.
First of all, though, call a number you are sure is Wells Fargo and make sure that you were talking to someone from Wells Fargo the first time.
Yes, I called the 800 number to verify this was real. It is. Everything in my OP is real.
And yes, THIS is what is strange. I’ve been racking my brain trying to figure out WHAT I did, and I can’t figure it out. I never use that card.