I'm trying to create a devtest-lab in azure but it keeps failing
I tried another region (West US 2) and that didn't help either:
I was able repro the issue and I reached out to related Microsoft Team. I got an information that it was related to outage of Azure Storage today where subset of customers were impacted may have received failure notifications when performing service management operations - such as create, update, delete - when attempting to manage their Storage Accounts.
As Azure DevTest Lab creation does create Storage Account and failure in that creation caused the error you got.
However, the Azure Storage Account Issue is now resolved. I am able to create Azure DevTest Lab successfully now. Please try again from your end now and you must not face an issue.