Goto transaction SE18 :

and check if you have an PT_ABS_REQ BAdI active:

double click on your enhancement implementation, and navigate to the technical details there:

Here you can see the respective class from your enhancement and via double-click you can again

navigate to the same

Into this highlighted interface method IF_EX_PT_ABS_REQ~PROCESS_MESSAGES (which came via SP)

you need to copy the coding of the fallback-class of the standard BAdI implementation from:

CL_PT_ARQ_REQ_EXIT . To sum up: in our example here, the exact coding of method

IF_EX_PT_ABS_REQ~PROCESS_MESSAGES from class CL_PT_ARQ_REQ_EXIT

needs to be copied to the same method of class ZCL_PT_ARQ_REQ_EXIT .

if you navigate to the method implementation (in ALL of the active BAdI classes), the coding should

be like in the following screenshot: