AppStream 2.0 not persisting settings in S3 bucket

Hi All,

I have an AppStream on-demand fleet with both User Application Setting persistence and S3 Home folders enabled on the associated stack. When creating the stack, both the buckets were created in S3 as expected. I have an S3 gateway endpoint setup for access to the buckets with routes implemented to the private subnets of the AppStream fleet. The policy attached to the endpoint is the one recommended on the AWS docs for AppStream. The fleet platform is the Windows Server 2019 base image.

When users connect to AppStream, the home folders are created no problem in the bucket and users can access their saved files. The app persistence settings however don't appear to be working correctly. No folders are created in the bucket at all and any changes to the user's appdata don't persist between sessions.

I have tried recreating the App Settings bucket, amending the policy on the S3 endpoint to full access but can't seem to get anything to create within there. Just looking for any suggestions for further steps if possible as I seem to have exhausted the available documentation and not found any answers.

Thanks in advance!