ChangeTrustNotAllowed Error

Question

I'm trying to run a Change Trust operation in order to add a trustline, but it throws me a ChangeTrustNotAllowed error which I can't reference in the documentation.

Here's my Transaction Envelope and the Transaction Result.

I attach the error message:

{
  "type": "https://stellar.org/horizon-errors/transaction_failed",
  "title": "Transaction Failed",
  "status": 400,
  "detail": "The transaction failed when submitted to the stellar network. The `extras.result_codes` field on this response contains further details. Descriptions of each code can be found at: https://www.stellar.org/developers/learn/concepts/list-of-operations.html",
  "instance": "horizon-001a/Fm1q5QnVH4-156771048",
  "extras": {
    "envelope_xdr": "AAAAAJQ8YCVmD7CrwMmGcOQ/FQWPuDebKSAp5W1uYYfT50ycAAAAZADx67sAAAAQAAAAAAAAAAAAAAABAAAAAQAAAACUPGAlZg+wq8DJhnDkPxUFj7g3mykgKeVtbmGH0+dMnAAAAAYAAAABVFBDAAAAAACUPGAlZg+wq8DJhnDkPxUFj7g3mykgKeVtbmGH0+dMnAAAAOjUpRAAAAAAAAAAAAHT50ycAAAAQOl23ijxXLlony2S+/trxM27gG1Dw7CfHPpQrzt/etor41+FYm+oO4+/W7WcRWTRfZpZkgLwkmfl7srLsjDGFg8=",
    "result_codes": {
      "transaction": "tx_failed",
      "operations": [
        ""
      ]
    },
    "result_xdr": "AAAAAAAAAGT/////AAAAAQAAAAAAAAAG////+wAAAAA="
  }
}

Answer 1

It looks like you are trying to create a circular trustline, sourceAccount and issuer are the same.

A trustline can only be established from one account to another. Try creating one more account and set up the trustline between them.