This is a known 'issue'. Google (and others) use several techniques to improve location detection, like mapping wireless networks (technically BSSIDs) to a location. That is done through the cars they drive around for Streetview, but also by crowd-sourcing of the devices that have multiple location methods like cellular, GPS, wifi, and upload what they see.
I have seen this in events, where our phones (and those of the attendees) showed the location of where the APs were before, and with demos where I even have seen my location jump between Europe and California US near the Aruba HQ. Apparently, the APs were used there before.
When you search on the internet, you will see that people have similar issues when they move houses and their location is still at their old house for a few days.
Till now, I haven't found a good solution to fix this 'on-demand', but if you wait a few days it will auto-correct if as many as needed phones have reported GPS+cellular+WiFi location. It might work (but you never know) to use Google maps to enable GPS and walk around the perimeter of your building, while WiFi is enabled as well. You probably need to disable opt-outs for the sharing of your information and location history. It's nearly impossible to contact Google and trigger an immediate change of location, and probably by the time you found out, the issue has disappeared as enough new data has come in.