My employer forgot to give me hra exemption what to do now

Dear All

My Employer Delhi University forgot to give me HRA exemption inspite of submitting all the rent receipts on time. Now my form 16 has no mention of HRA exemption on it.When enquired in office they told me that was a mistake and advising me to file my IT Return now as per the current form 16 and later file a revised return to get refund.I am very worried because last date for filling return is 31st july and dont know what to do.Kindly suggest the appropriate action.My total HRA Exemption is 170000rs.