Thanks for getting back in touch with us in the Seller Community, @saydad. Transactions on your point of sale can't be deleted, only refunded. As you can imagine, it's important for your point of sale to keep a record of all transactions and to prevent sales to be deleted by mistake, or on purpose, by a staff member for instance. That being said, we've received feedback like this before, so I'll add your vote to this feature request.
