SRM SUS PO service confirmation account type 'U'

Hi masters.

On SRM 7.0 /SUS  and ECC 6.0  the user create a PO with Undefined Catt and this is send to SUS is OK .  

the vendor to confirm the service the problem is when Service Confirmation come to ECC end with the next error

account assignment exists for service line 0000000010 

Is posible charge de Entry sheet and when user accept change the count.    

thanks on advanced.