16 yr old unserved warrant and IAD

What is the name of your state? What is the name of your state? NC i recently found out i have an outstanding felony warrant as a result of a partnership falling apart in 1986--since 1986 i have been searched through NCIC 20-30 times by various agencies--these searches have come up negative until now!!?? how can the county withhold a warrant for 16 years before putting it into the computer--in 1995 i had the good fortune to take a 5 year vacation at the expense of the feds--during that time, under the interstate agreement on detainers (IAD), i was to have been afforded the opportunity to resolve any unserved warrants--i was not given this opportunity due to the county/state not coming forward with this warrant when notified i was in custody--i am trying to get my life back in order--including a child custody issue--and this could really cause problems--how do i approach this DA and argue this thing to just go away??