Add/remove line to Manufacturing Order-BOM components

What are the steps to edits BOM lines on an MO?

Pick components, manufacture and then store products (3 steps) - we have 3 step manufactuing process set up.

What are the steps to reproduce your issue?

We create an MO and save. Picks are created.  Before the plan of the MO and WO's are created from the BOM, we need to edit a line and add/remove BOM components. Odoo server error is received when we try to save the MO.

What is the current behavior that you observe?

Odoo Server Error - Validation Error
The operation cannot be completed:
- Create/update: a mandatory field is not set.
- Delete: another model requires the record being deleted. If possible, archive it instead.

Model: Stock Move (stock.move), Field: Source Location (location_id)

What would be your expected behavior in this case?
We Should be able to add/remove lines to the MO component. This is out of the box functionality.

I have gone thru runbot demo v12 instance and function should be there to edit lines.