Databricks Job owed by service principal, failed to checkout from Git repository : PERMISSION_DENIED

Hello,

I'm working as Data Scientist and I have some jobs to run on a Databricks.

I've created the jobs, which run the code store in an Azure DevOps repo. Everything went well, when I tested the jobs, all worked well.

I transfered the ownership of the jobs to a service principal (this way : https://learn.microsoft.com/en-us/azure/databricks/workflows/jobs/how-to/run-jobs-with-service-principals), and since, I get this error message : 

First I though it was because the service principal wasn't in the list of authorized users with "Read" permission over the repo that contains the code, I added the service principal as a user in my Team's Group, and now it has the following permissions over the repo (I followed this tuto : https://techcommunity.microsoft.com/t5/azure-devops/how-to-grant-service-principle-access-right-to-azure-repos/m-p/3744052) :

But I still get the same error.

So what's happening ? How can I fix it ?

Thank you

Charlotte