Redshift serverless stuck in "modifying" status

I turned off "publicly accessible" on my redshift serveless workspace a few hours ago and it is still in status "modifying". I cannot delete it, or delete VPC resources connected to it. I have found other questions about this but no answers.
I've looked at everything I can find in the console (redshift serverless, cloudwatch, vpc/network,...) and tried deleting all related resources (after waiting 2+ hours). Also tried the cli and get

An error occurred (ConflictException) when calling the DeleteWorkgroup operation: There is an operation in progress. Check the status later and try again.

AWS says I need to purchase a support plan to enter a support case. Is that true? Is there another way to get resources deleted or reset or get the "operation in progress" canceled? Or even find out what that operation is?