Difficulties with onboarding in Azure DevOps Server 2022

[asfswa]

How are you running Renovate?

Self-hosted Renovate

If you're self-hosting Renovate, tell us which platform (GitHub, GitLab, etc) and which version of Renovate.

Azure DevOps Server 2022; Renovate Version 39.13.1

Please tell us more about your question or problem

I have configured Renovate Bot to keep track of dependencies in a number of repositories. I'm not using the autodiscovery mechanism and have manually listed all repositories. For most repositories the onboarding process was successful.

In those case where the onboarding was not successful, the situation is as follows:
Renovate Bot creates an onboarding PR that adds a default renovate.json file to the repository. After I approve the PR, Renovate Bot adds a comment to the PR ("Renovate is disabled
Renovate is disabled because there is no Renovate configuration file. To enable Renovate, you can either (a) change this PR's title to get a new onboarding PR, and merge the new onboarding PR, or (b) create a Renovate config file, and commit that file to your base branch."). On subsequent runs of Renovate Bot the repository is ignored (see logs).

I tried following the recommendations from the comment but it is not possible to change the title of closed PRs in ADO and there is a configuration file present in the repository. Editing the renovate.json file dit not help either. I have tried to start over by reimporting the affected repositories into ADO to get rid of the PR history and the configuration file. So far without success as I keep running into the same problem.

Logs (if relevant)

Logs

...
DEBUG: config file not found (repository=<ADO-project>/<repository-name>)
DEBUG: Found closed onboarding PR (repository=<ADO-project>/<repository-name>)
DEBUG: Repo is not onboarded and no merged PRs exist (repository=<ADO-project>/<repository-name>)
...