Help me, I can't activate BADI Z_SDK_SCHED_ST_CHD in SE19

Hi guru

My Solman environment is 7.0 SP23, I follow on note 1275036 to create BADI Z_SDK_SCHED_ST_CHD but when I clicked activate button, I found error message and double click to look into error message detail as the following;

There is already an active implementation for the implementation class CL_IM_AGS_SDK_SCHED_ST_CHD

Message no. ENHANCEMENT478

Diagnosis

The implementation class you have used already exists in another BADI implementation that is active.

System Response

Activation of this BADI implementation is not possible.

Procedure

Assign a different implementation class or deactivate the other BADI implementation that uses this class.

Please help me how to proceed this problem

Thank you very much