It can happen, as
@gbb suggested, pull the tape back and look underneath, the spoke may be protruding above the top of the nipple, which could cause this, if it does, then either file it down or use a shorter spoke.
I also presume that you are using rim tape that came with the bike, probably a thin plastic? That stuff is frankly dreadful, swap it for Velox cloth rim tape, it's a bit heavier, but you won't ever have any problems with it.