http://www.qatarliving.com/answers/visas-and-permits/how-could-i-lift-my...

Did you ty calling the bank and find out a settlement with them? Did you try contacting your embassy here in qatar to see if they can actually get an update in your case? Did you try talking with the company HR / PRO/ Mandoop and ask them to find out your real situation?

Instead of sending a letter it would be better to call the bank.

Regards!!