Complaint Review: fingerhut/safeline account protection

The Safeline Protection insurance I bought is in effect until  October, but Fingerhut collection dept. cannot seem to the the message...they call and send late payment letters almost every month, and even though I tell them what they should already know, the badgering continues.  I am  getting really tired of the whole process. 
I am permanently disabled, and recently fell, broke my leg, and am currently  doing in-home therapy to get out of a wheelchair. 
I got a letter from them before this incident, and they now want ANOTHER signed  statement of disability from my doctor, even thought the disability is already documented as permanent.  I don't know what is wrong with these people, but they should learn to communicate between departments.