fatal: could not read Username for 'https://github.com': invalid url

I am trying to setup auto merge for my main branch whenever something is pushed into the development branch using gitaction. This is my gitaction file:

name: Auto merge
on:
  push:
    branches:
      - development
env:
  # replace "github_username" with your GitHub username
  # replace "github.com/username/repo.git" with your GitHub repo path
  # do NOT replace ${{secrets.GITHUB_TOKEN}}, GitHub will take care of it
  MY_REPO: https://my-username:${{secrets.GITHUB_TOKEN}}@github.com/organisation-username/repo.git

  # replace "long-lived_branch_name" with your branch name  
  MY_BRANCH: development

  # replace it with the path to master repo
  MAIN_REPO: https://github.com/organisation-username/repo.git

  # replace "master" with your master branch name
  MAIN_BRANCH: main

jobs:
  merge:
    runs-on: ubuntu-latest

    steps:
    - name: Merge with master
      run: |
        git clone ${{env.MY_REPO}} -b ${{env.MY_BRANCH}} tmp
        cd tmp
        git config user.name "Automerge Bot"
        git config user.email "gcpabia@gmail.com"
        git config pull.rebase false
        git pull ${{env.MAIN_REPO}} ${{env.MAIN_BRANCH}}
        git push

The thing is I belong to the organization as owner, so the repo isn't in my personal account. I keep getting this error:

Run git clone ***github.com/organization-username/repo.git -b development tmp
Cloning into 'tmp'...
fatal: could not read Username for 'https://github.com': No such device or address
Error: Process completed with exit code 1.

My suspicion is that the issues might be the different usernames I am using to carryout this operation and have switched between that of the organization and my personal account with no success.

Any pointers as to what I am missing.