I tried to cancel today. I had an Uber Eats order arrive very late and the food was cold and soggy. I still ate it (it was borderline acceptable), but I was slightly unhappy that they didn't give me the $5 credit which is an UberOne benefit for late orders.
I went through the menus, and got a chat agent, who had no clue about Uber One benefits, and lied about being unable to help me through chat, and needed to transfer me to an email based agent, just to end the chat. After this, I went to go end my Uber One membership, and they offered me 90% off my next month to give them another chance. Fine.
I started another chat, and got yet another clueless agent who didn't understand the issue, but refunded me the entire order and gave me $15 in Uber Cash, so now I am beyond made whole.