I found the solution everyone. It worked for me I hope this works for you as well!
well the problem was that my accounting software was giving document summary in the GSTR1 excel sheet as well. Please be cautious and dont give any details about this in the excel as you have to manually write the data of "docs" section in the gstr1 portal online version. I think this was causing my json file to be corrupt. and error was resulted i have the proof of such 
I am uploading the excel template and copy all data into that one and i am sure this problem will be solved or else give your data to me i will generate your json file for free. Here it is my email id - prashinv2009 @ gmail.com
Don't confuse yourself that the question remains same.It becomes easier if you comprehend the way of my answer it's easy.
CAclubindia
