So I bought earlier today 5 Premium Chests and in their description they don't require a key to open.
However I couldn't open them and when I bought some keys they became available (I had 3 keys and could only open 3 of them even tho I had 5 Premium Chests).
Then when I ran out of keys and still had 1 Premium Chest left it became unavailable to open.
Note that in the past I could easily open Premium Chests with no keys and this bug probably happened because of recent bug with purchasing chests that gave PROJECT: Tokens where you could buy chests & keys but the game didn't take your RP away.
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