CKMM issue error: C+151 (Price control (new) must be S for price determination...)

Hi, everyone:

I have two questions:

1. What are the consequences to use CKMM ?

2. The scenario is as follows:

    First, I change the Price Determination from 3 to 2 by CKMM

   Second, I want to change the Price Determination from 2 to 3 by CKMM, but the system issues an error: C+151 ( Price control (new) must be S for price determination (new) 3 ).  How to solve this issue?

Thanks in advance.