Note, this is one IFS App10 Upd19.

Surprisingly when I create the line manually it works, this error only happens when I pasted employee from another organization.

Wondering if this a BUG?

Self Answer: 

I still have no idea why the error happens, but at least there is an alternative way to do that.

Go to:

Organization and Position Assignments > Filter as usual > Select all person you want to reassign > Right click > Change Assignment Assistant

Hi,

If you want to move one employee from one organization unit to another it is important that you set the end and start dates correctly.

• End date to the old - Save
• New line new assignment with from date the day after old assignment end date - save

This is what the assistant helps you with - my recommendation is to always use assistants when available.

If you overlap if could end up with the employee loosing his / her primary assignment and then you will get problems.

Regards,

Maria