How to test an Idoc even it is showing Status -12

Hello!!

Good Afternoon.

I have sent an idoc to the external systems, but my customer says that only 29 partners have been received and we need 70 partners.

But i have checked in we02, it is showing status 12.

How to track, the idoc with rest of the partners and the reasons.

How to test an idoc even it is showing status 12, and troubleshhot.

Waiting for your response,

Regards,

Ram