If I go to the Messaging app > Settings > Advanced there is an option called "your phone number".
I noticed that the number shown is not my actual phone number on my sim card. The number seemed somewhat familiar and I have a vague recollection of being asked for my phone number somewhere in my beginning days of using GOS in "some place" and I didn't like that so I put in a fake number. I think when I first put my sim into my phone with GOS the first time, it asked me to enter my "phone number" and that's where I put in this fake number (A very hazy memory that I could be wrong on). I have a faint recollection that this number might be that number.
So I tried to change the number in the Messaging app today. At first it didn't seem to stick. So I restarted the phone. Then when I loaded the app after restart I noticed that it hadn't changed. But then again the next time I checked it had changed to the new fake number I put in.
Then I was kind of browsing around in phone settings, and I checked Settings > About phone and I saw that the first fake number was also here. Now with this one I can't change it. Changing the number in the Messaging app doesn't fix this. I also can't seem to get rid of it.
Interestingly when I go to Settings > Network & Internet > SIMS and I disable "Use SIM" The numbers from both places disappear and "unknown" is shown instead.
When I turn "Use SIM" back on, both false numbers appear in their places.
I'm pretty sure this is not being pulled from my sim card. My sim card never had that number, nor are there any numbers saved on my sim.
Any ideas as to why this number is stuck and how to erase it?
On a side note, what is the purpose of the "My phone number" field in the messaging app anyways? What does it do?