GST mismatch ITC as per GSTR-2A (auto Table 3 & 5 thereof) and actual 2a (excel downloaded) 2017-18

Dear All,

Please help urgently,

We are getting difference between gstr2a yearly details auto populate and monthly gstr2a downloaded in excel file.  I matched all the details in month wise and only in 1 month i am getting difference rest all month are tally. Difference amt is very huge so please help me in this matter on urgently.

I called to gst portal helpdesk & cbic but no response received.