Hold the Power button for 20 seconds continuously.
Do not tap repeatedly.
Wait 30 seconds.
Then press Power once normally.
If it boots → sign in and immediately back up the BitLocker key.
Try entering Surface UEFI first
Hold Volume Up + Power
If UEFI opens and SSD is visible, attempt Recovery/Startup Repair.
If it still loops or the SSD is missing → request replacement immediately rather than spending hours troubleshooting.
Contact Surface Support for Business and Education customers
https://www.microsoft.com/en-in/surface/business/warranty-protection-plans-and-support