I have a 2007 harley davidon

Dont know how many miles or how well you maintain it,but its a possibility of the check valve in the camsupport plate sticking though thats more common in 88 inch motors,how well do you trust your mechanic shop,they should be able to pinpoint what happened,however if your not sure of your shop,I have two retorical questions,how long after your last service did it happen,and did you check to see that there was oil in it after it quit,they wouldnt be the first to 'forget"to put oil in it or maybe the drain plug came loose, thing is only the guy that tears it down will know for sure,but you definatly lost oil pressure, your idiot light should have been glowing