Hi Constantin Murarasu •,
Kindly check Environment Variables properly configured in your system.
If you have made any changes to the environment variables, restart the PostgreSQL service to apply the changes.
Update PostgreSQL to the latest version and retry.
If above does not help, I would recommend you to raise the question over PostgreSQL Community forum to get better advice.
Here on Microsoft Q&A, if you face any issue related to Azure Databases of PostgreSQL, then we could help further.
Thanks