How to reset Wi-Fi location history

Solution 1:

What you are referring to is called A-GPS (a for assisted)

I would try to Reset Network Settings.

Solution 2:

I believe this is actually something with their network. I had this issue when I was at Apple. They brought in a bunch of Cisco equipment that was configured in California to our store in Georgia and the location data always said it was still in California until they reset this on the network. Try testing it out on someone else's phone and see what happens. I'd ask your network administrator if this is something that can be changed.