I got a feeling the Prestige is either bugged or it is not shown in a good way.
Right now, I am at 6 stars (6* is shown above the word PERMANENT). I have Strong hand (2/5) and Deep pockets (1/5), both with yellow borders, showing 6* and the end of each update.
This can either mean, that I bought the upgrades for 6* (yellow border means "bought") or that I have to pay 6* to buy them (yellow border means "enough stars to buy"). As nothing happens once I click them, I assume I already bought them. In this case, the NEW price should appear.