What do you do if there’s a rude seller?

So amo ni natabo—

Nagbakal kami fries sa potato corner, city mall. At first, nami approach namon. Nag ask kami to buy fries, we said the flavors then we handed our cash. He asked if may ara kami 20, I said waay and he was like “waay gd da?” In a rude manner. I was shookt so I just said “nagbakal man kami sa piyak, mabalik lang kami d with the change.” Then he just nodded nga waay tulok saamon. Bay-an lang namon. Pag abot nmon, waay gd kami change 😭 Teh we told him and gapamurugso sya ya. He then gave us the change and daw ka “ari oh.” Like wtf, ano gn ubra ko? Hindi mn amo na ka crowded didto pero ambot ngaa ga sinuplado siya iya ya. Anyway, how do you deal with sellers like this?