IP geolocation does not give the location of an IP. It gives the most recent location of an IP when someone from that IP address signed up for a service and entered a location and then that service provider sold the database off to an IP geolocation service.
In other words, it gives the address of the last person to fill out a survey from your IP.
If you want your IP to be updated to your home, fill out every online newsletter subscription, survey and credit card offer you can find.