Flash disk says write protected and can't be formated, but it could be virus

Hi there, i have tried all the command and Redegit methods but none of them are working for me. In using the command, after i have typed the Disk clear readonly, it says it's successful but it's still the same and when i type in the command Attributes disk again, still the readonly says Yes. And on the Redegit method, the write protect value is already 0 but still my flash disk says it is write protected when copying or sending files to it. So please let me know if you have any solutions. Thanks