Bill is prepared the Lost month, bill is recived curent mont

Dear friends

one product  purchased in the last month it is send the Only DC. But the company is Prepared the On the Same date. But the company was not send the invoice. bill is recived in this month last month vat filing my dout is Bill is recived the date of entry or bill is prepared  date of entry. please clarifed the doute.

Ex: Bill is prepared date 15.07.2010, Bill is recived date 16.08.2010  in the two days which date or entry.

Thanking you

GOREDDY