Hi Tinhat
Welcome to the forum.
You might want to have a look at the following FAQ which explains where everything is;
www.benefitsandwork.co.uk/guides-for-claimants/faq/forum.
You need to send your fit note to the address on your letter from DWP, when you send it, write you name and National insurance on the note and send it by recorded delivery, don't send the original, send a copy.
Gary
