@Ke0dsd Fred, which device and version of HAMRS are you using? And are you using the POTA template?
There are some problems with the mapping that I believe @Jarrett is fixing in an upcoming release. But the POTA template should work well for you if:
(1) You enter your own grid square accurately and consistently for all QSOs in your logbook. (Be sure to turn on “Expanded mode” so you can see your own grid square.)
(2) You ensure a grid square has been entered for every contact, either representing their home QTH as pulled from one of the database lookup services (HamDB, HamQTH, or QRZ), or representing the park they are activating (automatically inserted when you enter “their park” number.)
Otherwise, when you say it isn’t working, can you describe what is happening?