Ya happened to me on 3 different heros I sent an email but no response I would like an explanation please , it shows a success and the star is added to the bar but then a few moments later its gone and I loose another star so I start with five stars and get six and the power up and then I drop back to 4 stars...wth is going on ?
I did use gems to do it so now I am out like 500 gems or more to this "bug" I am a high lvl VIP but if i cant upgrade my heros stars then it maybe time to shut down the money train to Tynon....