Router indicating wrong geographic location

Four computers in home, all connect to same router W-Fi. Checking location, all computers indicate they are located about 350 miles from our home. Our cell phones (Verizon) all show correct location. I am guessing that the Comcast modem has the wrong location, and passes that on to our computers? Is there a way to update the Comcast router with the correct address/location? I tried a simple reboot of the modem but that did not work. I tried chatting with Comcast Tech but that did not work either. Can anyone offer some guidance?'

Thanks!

Howard