Produt Order doesn't tranfer to APO

Hi

We had a problem about production order.

We run SNP heuristics in APO,and created plan order transfer to R/3,and Plan order is converted to production order in R/3,

But now the problem is ,plan order convert to product order and doesn't transfer to APO,so the plan order is still remain in APO,no production order.

Maybe because of different between APO plan order and transferred to R/3 plan order?

(The product some product orders were transferred to APO,but some doesn't ,so it maybe not because master?)

Do you have any idea?