Rectification of mistake u/s. 154 of the I T Act, 1961

Return of income for A. Y. 2010-11 was processed u/s. 143(1) of the I T Act disallowing TDS on Salary(TDS deducted by a Bhutanee's Co. & Deposited to Bhutan Govt.) , raised some demand for payment.
A rectification petition u/s. 154 was rejected by A.O. citing that "You had to claim relief u/s.90/91 of the I T Act to avoid double taxation. After verification of return filed by you, it is found that you had not claimed relief u/s. 90/91 of the I T Act."
Now, my question is there any hope under It Act and law to overcome this situation?