Hey Chandra Sekar,
Thanks for getting in touch and telling me what happened. I get how frustrating it is to get a new device only to find out it's got problems like a bulging battery and a busted motherboard, specially since you hadn't even used it.
First, see if your warranty is still good. It's worth a shot even if it's been a while. https://support.microsoft.com/devices
Microsoft also has a Microsoft Trade-In Program where you can trade in your old Surface Pro 7, even if it's broken, and get credit toward a new one. Check if you qualify here: https://www.microsoft.com/en-us/store/b/microsoft-trade-in
. Keep in mind that the extra cashback deal for trading in a device for a Surface Copilot+ PC only lasts until September 30, 2025
If your Surface is out of warranty, Microsoft might still offer to fix or replace it for a fee. Please keep in mind, Microsoft Surface devices do not come with a globally applicable warranty, so the service provided might change depending on your location.
Hope this helps clear things up!
If it did, please mark it as the Accepted Answer so other people in the same situation can find it too.
Best,
Jeric Sobrino
Microsoft Community Support