Payment method seems to be right but is still get failed even though did everything as it asked

I tried installing picsart, nothing important. Asked me to add payment method (which was already added ) , than asked me to verify it,did so and than it gave me a note that it was already there and i needed other one - added new method and it got failed like previus one . Everything seems to be right with info and all.i think its some kind of a bug that needs to be fixed . Could you tell me what would be the best solution?