Hi, I'm Bianca, an Independent Advisor.
There are a lot of reasons why a disk is write-protected. It maybe full or has a virus on it.
To be safe, I suggest that you run the Microsoft Safety Scanner as this tool can find, remove, and reverse the changes made by a malware which might be causing this problem. Download and follow the steps from this link: https://docs.microsoft.com/en-us/windows/securi...
You can also try removing it using CMD.
Press Windows Key + X on your keyboard, and select Command Prompt (Admin) from the menu.
Type diskpart and press Enter.
Type list disk and press Enter.
Type select disk #(ex: Disk 1) to select the disk which is write protected and press Enter.
Type attributes disk clear readonly to change the disk’s properties so that it is no longer read-only and press Enter.
Type exit and press Enter twice to exit Diskpart and Command Prompt continuously. Re-plug your USB flash drive to check if the write protection error is solved.
For your reference:https://www.diskpart.com/windows-10/the-disk-is...
Note: This is a non-Microsoft website. The page appears to be providing accurate, safe information. Watch out for ads on the site that may advertise products frequently classified as a PUP (Potentially Unwanted Products). Thoroughly research any product advertised on the site before you decide to download and install it.
I hope this helps. If not, let me know if this does not work or if you've tried this already. I might have another possible solution to try after this one.