Above exception will come when you commit all the changes of different project by using single commit.
Below is scenario where you can avoid such exception by suing below procedure
If you are trying to mass changes to C project in loop. Then you have to lock each project and then do changes. Then commit and then unlock the project. Use below procedure when you are in loop.
1. CALL FUNCTION 'ENQUEUE_ENQ_CGPL_PROJECT'
EXPORTING
mode_cgpl_project_enq = 'E'
external_id = pv_proj_extid
2. Do the functinlaity which you want to c-project means status change, add staff like this.
3. TRY.
REFRESH: i_return.
CALL FUNCTION 'BAPI_CPROJECTS_COMMIT_WORK'
TABLES
return = i_return.
CATCH cx_dpr_fatal_error.
4. CALL FUNCTION 'DEQUEUE_ENQ_CGPL_PROJECT'
EXPORTING
mode_cgpl_project_enq = 'E'
external_id = pv_proj_extid.
