Hi @Viet Tran
To troubleshoot your issue, I have some questions to confirm with you:
1)Could other participants see their shared screen normally?
2)What is your version of Teams client? Classic Teams or New Teams?
3)Does this issue persist all the time?
To exclude the client issue, we recommend you try to use Teams web client to see if it can be reproduced. If there is no issue in Teams client, we firstly recommend you try to follow these steps to clear your client cache file to see if works:
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