Card dispute

I'm disappointed by how Absa is doing. I used Uber on 26th December 2019 and was charged twice. I then sent Uber and email they said it would be removed after a few days. A few days later I connected Absa to see if they could help me since I was using my card after speaking to 2 agents on the phone they said I need a letter from Uber stating that I don't owe them. I'm not sure if they understand that they don't have a direct number or email to connect them. Asked if they can do card purchase dispute they said they can't.. I was using another bank before switching to Absa and they have a department that liaison on behalf of the client if they can't dispute the transaction themselves I'm not sure what to do currently because I can't get hold of Uber. I'm just trying to understand what I need to do