Cant print PO - wrong page format

Hi all

I have a smartforms to print PO.

I encounter this problem which some PO cant be print while some other PO can be printed.

Its quite confusing since only some cant be print.

Below is the message:

Form TXT_CONTACT has wrong page format.

Message no. SSFCOMPOSER026

Diagnosis

Form TXT_CONTACT has a different page format than the forms output previously but has been added to the same spool request.

System Response

Form TXT_CONTACT ist not processed.

Procedure

While forms are formatted (FM SSFCOMP_OPEN to FM SSFCOMP_CLOSE), the page format must not be changed. All forms within one spool request must have the same page format.

The first page format used, in this case paper format , is applicable to all subsequent forms.

Please guide me.

Thanks in advance