Why can’t I use Apple Pay for uber

See if this helps:

https://help.uber.com/riders/article/paying-with-apple-pay?nodeId=592106a5-d512-43b0-9ba7-3382989ede61

Note that you SILL need a credit card on-file or a cash balance.

Uber generally supports Apple Pay; however, availability may vary by location and app features. Ensure correct settings, regional support, and app updates for the best experience.

Uber is a preferred partner with Apple Card Mastercard, so the merchant definitely accepts Apple Pay. What issues are you having using Apple Pay?