Hi,
Thank you for posting in Microsoft Q&A forum.
1,Per my experience, it may be something to do with the location services. You can try to create a security group for the users in that location and push a static time zone to them. Similar threads for your reference:
Time-zone set automatically keeps changing
Windows: The Sands of the Time Zone
2,Please check if you have set the “Configure Time Zone” option under Settings Catalog -> Time language settings policy to change time zone. Refer to:
Configure Time Zone using Intune for Windows Devices
Thanks for your time. Have a nice day!
Best regards,
Simon
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