Bad service

I had transferred money to an incorrect external bank using my capitec app.

When i requested a reversal within minutes of doing that capitec which is my bank was unable to help me instead they sent me to the other bank to go request a reversal how do i request to reverse a transaction with an external bank that i dont bank with.

The external bank sent me back to Capitec to tell them that they can only consult their bank when they get a directive from my bank which is capitec because the funds are there.

Capitec refuses to reverse that the money saying they dont offer that service.