We are facing an issue with Q&A feature in webinar, it is showing the error "There was a problem reaching this app", i checked the logs and it seems to be issue from the backend.

Hi @Mohammed Darras,

Thank you for posting in the Microsoft Q&A Forum.

From your description, I’d like to gather a few details to better understand your situation:

1- May I know which location you checked the logs? If possible, could you please share the key points related to the error message (remember to remove any personal information).

2- Did the error appear immediately when you clicked Q&A, or was it working before and then failed?

3- Do the affected users have Viva Engage licenses? If possible, could you also confirm whether Teams allows Viva Engage in your tenant settings (via Microsoft 365 Admin Center and Microsoft Teams Admin Center)

To check, please reach out to your Global Admin (the person who manages all accounts in your organization). If you're unsure who the Global Admin is within your organization, you can find guidance on locating them here: How do I find my Microsoft 365 admin? - Microsoft Support.

4- Have you tried testing on other webinars? If yes, does the same behaviour occur there, or is it only happening in this specific webinar?

5- Which Teams version are you using (desktop app or web)? If possible, could you test on the other version as well?

Thank you for your time and patience, I'm looking forward to your response.

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Hello @Mia - Tr

Please find below my answers:

1- I have checked from teams desktop app logs and network logs from browser

from teams web browser console logs:Error(s): 500014 - Description: AADSTS500014: The service principal for resource 'https://web.yammer.com/teamsmeeting' is disabled. This indicate that a subscription within the tenant has lapsed, or that the administrator for this tenant has disabled the application, preventing tokens from being issued for it. REMOVE PII

2- it is loading for a bit then we receive the error, during which browser network log show 400 responses. its new deployment.

3- license assigned.

4- same behavior on multiple webinars

5- I tried desktop, web and mobile with the same results.

regarding the error from the console logs, can you point me what to check exactly,

Thanks