Azure - A system maintenance operation is in progress

Recently while changing the pricing tier of one of the Azure databases I faced following error:

Operation name: Update SQL databaseError code: 45197Message: A system maintenance operation is in progress on server 'servername' and database 'databasename.' Please wait a few minutes before trying again.

I tried it again and again but was facing the same message. Ultimately it was resolved by the Microsoft Product Group team efficiently and in due time.

There could be different reasons for the issue to occur but this was caused because of following reason as per Microsoft:

When a database’s performance tier is changed, the database is moved from a container with the old performance tier to a container with the new performance tier.  The old container is then cleaned up at the end of the process.  In this case, cleaning up the old container was not making progress.

It was mitigated by the MS support team by manually forcing the cleanup to occur.

As of now, we do not have access to check if the cleanup was not done properly, and in case if it happens again, cannot do the cleanup process ourselves. So if you face the same error after multiple attempts I would suggest raising a support request with Microsoft.