After working very hard to pay off my Sallie Mae XXXX loan in full XXXX XXXX, they promised that a payoff letter would arrive within XXXX days. No letter was ever received. Each time I call back the customer-no-service promises that a letter will be sent soon. It has now been XXXX days and the account is STILL OPEN! I called today and asked to speak to a manager. When I insisted that they close out the account or else a formal complaint would be filed they hung up!