Hi Suchi and Chitra
Sorry for delayed response.
I got my EAD Approved,
Write a letter immediately along with RFE Documents.
Mine took around 3- 4months after sending the letter.
After sending the letter and documents they transferred my case from Nebraska office to California office ,That gave me a hope of that my application is still under consideration.
and Finally got my EAD approved .
Thank You!
Good Luck!