request of a closure letter

I have been requesting a closure letter from edgars since the 21 December 2020,they are telling ne that they have send the letter,(the paid up letter,which does not state that the account is closed)they fail to send it,everytime I make a follow up m being told about 72 hours,after that 72 hours I still don't receive the letter.they have delayed my whole process of getting a loan