This card ( or or something like that) once was a trophy reward. Then the trophy was deleted and this card is (theoretical) now only available in the market for 3.000 crystals.
The problem: When I try to buy the card and click on it then the card is not available. So it cannot be bought. Since I need this card or the trophy "the hero" I really need the card.
The bug is known since a year, so fix it! The card is needed for a trophy!