Sub-assembly is not coming up for particular assembly. Even it's showing in different assemblies and

MMMA--->Main assembly

-SSSA--->Sub-assembly

MMMA is main assembly and it has demand  on it and demand is creating Planned orders and these planned orders cascade demand to sub-assemblies under main assembly(MMMA). But there is one subassembly SSSA is not showing on PLANNER workbench for MMMA.

This subassembly SSSA is also part of other assemblies too. and all of other assemblies except MMMA have no problem and demand is cascading from higher assembly to SSSA.

Note: Collection workbench is showing the SSSA under MMMA in ITEM FORM under components. But ASCP plan is not showing the SSSA