Tip 0 and see what kind of service you get the next time.

I used to work food delivery and naturally the customers ordering takeout at fancy restaurants would always tip 0 to the restaurant even if they tipped me for delivery.

I quickly found myself ignored by all the workers at those restaurants, orders take an hour extra to fill, no one talk to me, etc. eventually I learned to tip out of my own tip because my next service is contingent on the prior tip.