Thanks for the waiting and founding, but I am afraid this issue is not easy as we thought before. After dig into it, it tied to Census Tiger data which our geocoder original data is from, even in the latest tiger data, there are some invalid zip codes (about 400 records in all 34000) which Census doesn't update them yet, we will try to contact their development team for verification.
Currently, I think here are two options, one is we made an adjust list file on mapping the invalid and valid zip codes pair, then in the geocoder match results, once the zip code is not valid, then we replace it with a right one. The other one is we rebuild the whole geocoder dataset and during the build, we adjust the invalid zipcodes, but I guess rebuilting the whole data will take about one month in all.
So, if it is urgent for you, take the option one is a good idea or you can wait till we rebuilt the new dataset. I've attached all the invalid zip codes if you want to have a look. I have no idea when we will finish the mapping list, but we will do our best.
invalidZip.txt (2.88 KB)