Canceling current I-765 form and filing a new one

Dear all:
I am a student of Texas A & M University. I was about to graduate in May'15 but due to an accident, I am graduating this August. I had applied for my EAD card in early march for OPT date starting 15 June. Unfortunately because of deferring of my graduation, has led me to cancellation of my EAD card. I am facing severe difficulty in cancelling this and request your advice.
Here is the step by step of my procedure and decisions I had taken:
1. Sent my OPT docs via mail around 9th March ( I gave my OPT start date as of 15th June), the USICS system showed they were received as of 17th March according to their website.
2. On End of April, I decided to cancel my graduation thus cancelling my OPT paperwork because of my injury and inability to defend/complete research so I informed the ISS (international student services) regarding this. They told me they will notify USCIS
3. Around mid May, ISS calls me and tells me USCIS has not responded so I need to go and call them in front of the adviser. The USCIS immigration service officer advices to send hard-copy for petition for withdrawal of the case. The next day, ISS sends the hard copy with request letter , the sevis fee receipt as well as other supporting documents to USCIS. on 1st June, I call USCIS to ask if the hard copies have been received, but they answered negative and recommended me to send them soft copy through email. This I did it on 1st June itself.
4. On 4th June, I called again if the paperwork was received in soft or hard copy, but the immigration officer told neither was received. So, I demanded to speak with higher immigration officer. I talked with higher officer and he put a note in the system stating my petition for with drawl
5. On 7th June I called up to ask if my case was taken up regarding withdrawal, officer told it was taken up and under scrutiny.6. On 11th June, I received status change for my petition "Request for Additional Evidence Notice Was Mailed".
Now I am stuck, I dont know what to do, I cannot apply for new one until the current one is cancelled ? OR I cant start my second OPT application irrespective of first one being cancelled. The USCIS is not clearly telling me what the notice contains. I am highly nervous and request for advice. Thank you. I look forward to a positive response from your side.
Hi Utsav,

I have the same situation. I sent a cancellation request to USCIS. What I want to know is, what was the procedure to get your I-20 back in the original form. Because when you apply for OPT, you get a new I-20 with a program end date on it. But when you cancelled the OPT application, you needed a new I-20 for continuing your course right? What was the procedure you or your International student advisor did?