how to add previous month purchase bill and claim ITC

how to add previous month purchase bill and claim ITC

Hello we have a unclaimed ITC bill of April (we didn't claim it in may as seller didn't uploaded his gstr1 ) when we trying to file gstr 3b in  june month  we noticed the bill has been uploaded (april bill) .how to change the filing month of that april bill to june with out changing bill date? so that i can claim itc in june ... i can see only bill date change option in purchase invoice .there isnt any option to select filing month/date