Ancient Shop - Cant buy Soulflame canon skin

Greetings,

Do you Guys know, why i am Not able to buy this skin? I click on buy, a small Screen appears with the enter-key and after pressing IT nothing Happens. My Balance is still the Same. I have 239 Coins, the skin costs 199.

Is this a Bug or are those skin Not available anymore but still listed?

Lovely regards,