Azure AI Foundry Assistant Playground "Unsupported Region" Error After One Day of Usage

Hello Team,

   We created an AI Foundry in the EastUS2 region, and then we went to the Assistant Playground within that foundry and created three assistants. At that time, everything was working properly. However, the next day when we opened it, we encountered this screenshot issue.
```We checked our network settings thinking it might be a network problem, but the issue persisted. We also checked if there were any role-related issues, but everything appeared to be configured correctly there as well.

Thinking that maybe we created it in the wrong region, we deleted that foundry and created a new one in the France Central region. That also worked for only one day, and the next day it stopped working again."

**Summary of the issue:**You're experiencing a recurring problem with Azure AI Foundry where:

1. Assistant Playground works fine on the first day after creation

1. The next day, you get an "Unsupported region" error

1. This happened with both EastUS2 and France Central regions

1. Network and role permissions appear to be configured correctly

This seems like it might be a service availability issue or a configuration problem with Azure AI Foundry rather than a user error