You can also try this:
*********** sd card to your card reader and insert it to a computer,press the start button and search diskpart or just press the windows button+R then type "diskpart" in cmd, type "list disk" then press enter find the disk number of your sd card usually 1 , pag nakita mo na type mo "select disk 1" or kung anong number nakalagay dun sa sd card mo,pag natype mo na enter mo tapos type "attributes disk clear readonly" press enter tapos type "exit" press enter then try formatting your sd again,if that didn't work,well,May your sd card rest in peace