Revised income tax return after received refund

139(5) If any person, having furnished a return under sub-section (1), or in pursuance of a notice issued under sub-section (1) of section 142, discovers any omission or any wrong statement therein, he may furnish a revised return at any time before the expiry of one year from the end of the relevant assessment year or before the completion of the assessment, whichever is earlier :..”

Since the assessment is completed in your case, you wont be able to file revised income.