Complaint and request

I have a credit card that i am owing with african bank,i asked for a settlement letter stating the discounted amount to be sent to me as they told me i qualify for a discount.I called african bank the whole day being sent from pillar to post and i explained to each and every consultant i spoke to that i need the letter today because the discount is valid until today and the settlement is being paid by a certain company on my behalf.Some told me they wont be able to help me until they complaints department finally assisted me with a letter that states the discounted settlement.However by the time they sent it,it was too late,the company was already closed they can only process it tomorrow.The letter say its valid until 31/1/19.African bank can you kindly extend my discount to 1/2/19 so i can settle this account.If i receved the letter earlier i would have paid today.Please send it tomorrow on the 1/2/19 early to my email address