merge pr 1 by MERGE method failed for reason: refusing to merge unrelated histories

This error typically occurs when you try to merge two branches that have unrelated commit histories. To resolve this issue, you can try the following steps:

1. Ensure that both branches exist and are up to date. You can use the `git branch` command to check the branches and `git pull` to update them.

2. If the two branches have no common ancestor, you can try using the `--allow-unrelated-histories` flag with the merge command:

   git merge --allow-unrelated-histories <branch-name>

This flag allows the merge to proceed even if the branches have unrelated histories. Be cautious when using this flag, as it can lead to unexpected merge conflicts.

3. If you want to preserve the commit history of both branches, you can consider rebasing instead of merging. First, create a new branch based on the branch you want to merge into:

   git checkout -b <new-branch> <branch-to-merge-into>

Then, rebase the other branch onto the new branch:

   git rebase <branch-to-be-merged>

Finally, you can merge the new branch into the main branch without any issues.

Remember to backup your repository or create a new branch before attempting any of these steps to avoid losing any important changes.