香港冰室 (已結業)

Ordered one main dish and a drink. When I added one additional drink for take away, it costs more than it should. I saw the check before the drink came and ask for cancellation. The waiter started yelling at me and said he already entered the bill. Rude???? After that he talked some more Cantonese with his colleague which I didn't not understand then gave me another bill which -$2.. how weird??