I had six flats in one spring until I got my rim tape re-taped... one shop just re-installed the same old tape. First a hit-the-rock blowout of the tire off the rim and then... Two more flats. So I went to a different shop and whined until they put new rim tape on AND THEN put ELECTRICAL TAPE over the rim tape. Double protection against those nasty spoke holes. Few hundred/about a thousand miles, no more flats. I now strap duct tape on all my seat posts for emergency cover-the-spoke-hole incidents.

Sometimes it's just bad luck, sometimes it's figuring out a pesky mystery. Good luck!!!