update I went to an earlier character who had not done the questline for my kind of town and just started missile launching the whole town I did not lose any primm rep after the whole town was dead. Also with the character that did the quest line he still gets the discounts from Nash so maybe its just not showing up on the stat sheet as of the new patch? or they took out primm rep? I think rep is working as a sniped an NCR trooper and was shunned....although I did all the quests in the mojave outpost and did not get past nuetral(is that normal)
Primm has never had its own reputation. The only places out that way with their own rep are Goodsprings and Novac. The discount from Nash applies only if you put Meyers as sheriff, not either of the other two sheriffs (NCR, Slimm) give discounts, though placing the NCR directly in charge causes his prices to go up alongside getting a better stock.
It's normal that Mojave does not go up past neutral, typically even if you did all the Sloan stuff, as well as Mojave Outpost and attacking the prison, you will not get to Accepted before you finish at Boulder City (assuming you end in favor of the NCR).