Dear Jojit Yanga, I'm Henry and I'd like to share my thoughts on your issue.
If the label is physically damaged, Microsoft can’t regenerate the key directly from packaging — the only way is through proof of purchase with an authorized reseller.
Here is Microsoft's own documentation: Find your Windows product key confirmed for a damaged physical product key. Please note that the product key applies to both Windows and Windows Server editions.As you shared that your reseller cant do anything, but they are responsible for providing you with a non-defective product or a refund. Your purchase invoice and the photos of the damaged label are the exact evidence you will need to provide to them.
My recommendation is to contact the shop where you purchased it and ask them to initiate a replacement request via Microsoft’s Volume Licensing Service Center (VLSC) (note All Volume Licensing Service Center functionalities can now be accessed through the Microsoft M365 admin center) or OEM partner channel. If it was a genuine OEM key, Microsoft Support can validate the purchase and provide a replacement key once the reseller verifies ownership.
Hope this clears things up! If you find this guidance helpful, you're welcome to click 'Accept Answer'—it helps others find useful solutions too.