Unable to edit "ABC Assignment Group"

Hi Team, We are unable to update the ABC Assignment Group in the Lower instance. The Cycle Count Content is set to Sub inventory. The item was added after the ABC Classification Set was created, and we believe this may be preventing the ABC Assignment from being updated. We performed the following steps:

We performed the following steps:

1. Removed the existing ABC Classification Set.
2. Navigated to Manage ABC Classification.
3. Resubmitted the ABC Classification Set.
4. Tried to remove the existing ABC Assignment set from Group.
5. Tried to add the Manage ABC Assignment set it the ABC Assignment Group again.
6. Reran the related program, which completed successfully.