choices in list, limited by maximum rows: 50000 when trying to enter an item in ASCP workbench to re

We are on 12.1.3. A planner is entering a part# # X in the ASCP supply screen to add a manual planned order bt when he enters the part# X the LOV opens up and he gets a message choices in list, limited by maximum rows: 50000.He is unable to add this item to the workbench.How can we workaround this message and be able to add the part to release the manual planned order?

Thanks

Rahul