Can Ntelos activate a alltel branded 6900? help please

[Howlin]

I was given a brand new Htc 6900 phone . It is branded from Alltel . My question is How do i get Ntelos / Frawg Wireless to activate this phone? I went into a store and they tried to activate it . However i was told they could not flash it to the ntelos software . I started off with a htc 6800 titan . I later found that one to have a bad esn . However prior to this i flashed it with a win mobile 6.5 ntelos build i found on this site . Even after that they could not flash the phone at the store. What do i have to do to get this current phone activated ? I know the esn is clear and not on a banned list. My only issue is trying to activate it with a unlimited prepaid provider such as frawg / or Boost cdma . Which are all sprint in case someone actually didn't know . Any help would be appriciated .