PBE BUG. Buying 10 Premium Chest & keys + Bonus Gemstone twice with 1950 rp which is for one.

I bought 10 Premium Chest & keys + Bonus Gemstone and it lagged my rp didn't decrease then i just bought the set again. But this time the rp was decreased and i checked my loot and I had 20 chests in total. The 10 piece set has a buying limit of 1 each day.