GPS location is wrong

My mom got a GPS for her car and when she first started to use it she thought about using it to get home. It worked OK until we got almost to our house it wanted us to keep going down our road for about another .4 km to the end of our road.

Our address is 102 and it says our address is 736. Why?

For a rough drawn map

It isn't like it is a small mistake. We could deal with it being on the same road...