Qty Ord hold: Invoice line does not allow correction

Hi Gurus,

Purchasing options->Match Approval level is 3 -Way

Supplier site-->Invoice match option is PO

Tolerances: 0

PO QTY:100, unit price 50

Inv Qty:110

When i have this on the invoice, system created 3 holds Line Variance hold, Qty Ord,Qty Rec. I could clear the line variance but system does not allow me to update the invoice line to adjust the quantity. I do not want to update tolerances and PO since they are right. Can someone help in correcting invoice line Qty?

Thanks

Srikanth