Error: src refspec 'refs/gei/pull-requests/2/merge-clean' does not match any existing object

We are trying to migrate one repository from bitbucket to github using the following command:

```bash
gh bbs2gh migrate-repo --bbs-server-url https://git.ourcompany.com \
--bbs-project ${repoProj} --bbs-repo ${bitbucketRepoName} --github-org our-company --github-repo ${githubRepoName} \
--ssh-user renatoprado --ssh-port 2222 \
--ssh-private-key ~/.ssh/id_ed25519_company \
--aws-bucket-name migration-to-github \
--bbs-shared-home /home/appbox/data/git.ourcompany.com/shared \
--archive-download-host 10.20.8.110 --target-repo-visibility internal
```

And we got the following error:

```
[2023-12-13T18:50:57Z] INFO -- Migration started by renato-prado from https://git.ourcompany.com/projects/H4j/repos/structure/browse to our-company/structure
[2023-12-13T18:50:57Z] INFO -- Migration ID: 616c0454-3aab-452c-ac54-e81c013e3b77
[2023-12-13T18:50:57Z] INFO -- -----------------------------
[2023-12-13T18:50:59Z] INFO -- Git source migration started
[2023-12-13T18:51:43Z] WARN -- Stash ref inspection for files over 100 MB skipped: 20,546 refs is over the 20,000 refs limit for scan. If any of your stash refs contain files over 100 MB, this will cause your migration to fail.
[2023-12-13T19:09:04Z] ERROR -- Git source migration failed. Error message: src refspec 'refs/gei/pull-requests/2/merge-clean' does not match any existing object
[2023-12-13T19:09:04Z] INFO -- Git source migration failed
[2023-12-13T19:09:04Z] INFO -- -----------------------------
[2023-12-13T19:09:04Z] INFO -- Migration failed
[2023-12-13T19:09:04Z] INFO -- -----------------------------
```

The repository that we are migrating has:
- 7476 Pull requests
- 145 branches
- 44844 commits

Initially I thought that the error was associated with the size of the repository so I made a fork that didn't had the PRs, deleted some branches and was able to migrate the fork.

So we did the same with the original repository, we deleted some branches, tried to migrate but got the same error, so I think it might be related to the amount of the Pull requests but Frankly the error doesn't say much to me.