Won't automerge the PR. HttpError: Unprocessable Entity: "Can not approve your own pull request"

Hi! First thanks for your job. I’m facing a strange issue here that I cannot get rid of. I finally achieved to get the workflow running as it is creating a PR to Sync the repo. However, PR won’t be automerged and the GitHub Actions will fail. I tried two different configs, with different errors:

Config 1:

jobs:
  sync:
    runs-on: ubuntu-latest

    steps:
      - uses: tgymnich/fork-sync@v1.4
        with:
          owner: mikecao
          token: ${{ secrets.GH_PERSONAL_TOKEN }} # with public repo access
          head: master
          base: production
          merge_method: merge
          pr_title: Fork Sync
          auto_approve: true

Error 1:

Run tgymnich/fork-sync@v1.4
  with:
    owner: mikecao
    token: ***
    head: master
    base: production
    merge_method: merge
    pr_title: Fork Sync
    auto_approve: true
request failed after 4 retries with a delay of 60
Error: Failed to create or merge pull request: HttpError: Unprocessable Entity: "Can not approve your own pull request"

Config 2:

jobs:
  sync:
    runs-on: ubuntu-latest

    steps:
      - uses: tgymnich/fork-sync@v1.4
        with:
          owner: mikecao
          token: ${{ secrets.GITHUB_TOKEN }} # not my personal token
          head: master
          base: production
          merge_method: merge
          pr_title: Fork Sync

Error 2:

Run tgymnich/fork-sync@v1.4
  with:
    owner: mikecao
    token: ***
    head: master
    base: production
    merge_method: merge
    pr_title: Fork Sync
    auto_approve: false
request failed after 4 retries with a delay of 60
Error: Failed to create or merge pull request: HttpError: Unprocessable Entity: "Can not approve your own pull request"

Do you know what could be the problem? If it is about a misconfiguration from my side, I will be happy to open a PR updating the documentation when I realize of my error.

Owner repo: https://github.com/mikecao/umami My repo: https://github.com/tairosonloa/umami (you can see there some manually closed PR that the GitHub Action created while I was testing)