Cognizant Technology Solutions — Paid my dues but still did not receive my relieving letter

Hi, I have paid my pending dues of Rs 40, 052 on June 25Th to cognizant to get my relieving letter. They said they will release in 4-5 days after dues payment but till now( 13 days) I have not received any letter inspite of regular follow ups through emails and also calls to exit help desk.
I am clueless what to do as I am loosing days and my current offer is on hold due to this letter.