spools are not generating in sequence

Hello All,

We have a background job for invoice creation ( by using program SDBILLDL and the out put medium as 1 - print immediatly ) .Now the invoices are generating in increasing way but the spools are not generating in increasing way/ sequence with that the invoices also not printing in sequence way.

Could you please help on this ASAP.

Thanks in advance.

Regards.

Mr.Perfect