How do I solve a "Failed" message on a Redshift Serverless workgroup?

My workgroup shows a status of "Failed", and has done for a few days. I can still access the data in the Query Editor. I can successfully create a new workgroup, and the namespace associated with the workgroup is showing as Available. There are no controls for restarting or recreating the workgroup, or any way I can see to get out of the failed state.

I think a related issue is that the workgroup no longer has a VPC security group or subnets associated with it, which seems to have happened around the time the workgroup changed from publicly accessible back to private. I didn't change this.

I can't add a VPC security group or subnets because attempting to change those settings shows an error banner saying "ValidationException: Cannot update multiple configurations at the same time for workgroup default", despite having only completed the minimum required fields.