@Khushboo Kumari Thanks for posting in our Q&A.
For this issue, it is suggested to check health status under Tenant administration > Microsoft Tunnel Gateway in intune portal. Based on my search, please refer to the following article:
https://learn.microsoft.com/en-us/mem/intune/protect/microsoft-tunnel-monitor
Honestly, for such tunnel issue, it seems needed to check some logs on your device to find the root cause. With Q&A limitation, Q&A is not a good channel for such log analysis issue. Given this situation, we suggest to open case to do the troubleshooting. Here is a link with the steps to open case:
https://learn.microsoft.com/en-us/mem/get-support
Thanks for your understanding and hope everything goes well with you.
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