change message type E to W in VL09

I have a document PGI posted on 25.04, DO has actual GI date is 17.05 but posting date PGI is 25.04

But now is 18.05 and I want to reverse PGI by VL09 and posting date is 25.04

I got message

Cancellation date 25.04.2012 is before the goods issue date 17.05.2012

Message no. VL626

I could not change actual GI date in VL02N

I thought about changing message from E to W type. How can I change it.

Please help me and thank you so much.

Regards,

Gent.