Deletion of invoices in Gstr1 when the total invoice exceeds 500

Yuvitha (student) (80 Points)

11 June 2018  
we have wrongly filed april month turnover in may in gstr1. total invoice exceeds 500 so unable to delete the uploaded invoices using online option. how can we delete using offline and correct the mistake. can anyone help us regarding this issue???

thanks in advance.....