wrench ****** run by ******s ???

Took my Honda 750 for a tuneup because it was misfiring after paying R3134.00 it was returned with the same problem... when I complained I was told the bike smokes needs rings valve stem seals....the bike does not smoke ...I can prove it doesn't as i have the bike obviously....the engine I rebuilt top to bottom ...rings and seals were replaced with rebuild....they refuse to refund and offer insults ....this company seems to be run by amateurs... I would not recomend