Refund me atleast 330 how staff says it
"Staff" has nothing to do with this. Maybe this is a good moment to ask for "source of funds", like a bank would do. I'm pretty sure you scammed the money from someone else.
This "proof of payment" is only valid between buyer and seller, and meaningless to everyone else.
True, but since the other party didn't contest it and more or less confirmed it in
their own thread, I don't doubt this transaction happened between those two users.