Yes I understand what you are saying ,but this has been an on going thing
If you are lucky and get the star upgrade , and 1 to 3 days later you try another star upgrade with a 88% chance of success ,the stars you already had together with the new stars will be gone ,spend gems to buy more stars to try again another day and your stars will also be gone together with what you already had
Spend you money to buy gems ,which you use to buy stars and those stars will also be gone together with what you already had.
The game is just about taking your money ,then taking away what you paid for,and that's a 90% chance sure thing