Hi Ravi,
You have to check three configuration nodes as mentioned below:
1. Check in ECC if document type Z** is activated for compliance check in GTS plug-in
SPRO-> Sales and Distribution->Foreign Trade/Customs-> Global Trade Services Plug-in-> Control Data for Transfer to GTS -> Configure Control settings for document transfer
2. Check in GTS the GTS document type to which this ECC document type is mapped
SPRO->Global Trade Services->General Settings->Document Structure->Assign Document Type at feeder system or feeder system group level
3. Check if GTS document type is activated for License Management
SPRO->Global Trade Services->General Settings->Document Structure->Activate Document Type->Activate Document Type for Legal Control
I hope it helps. Let us know if you are still not able to make out.
regards,
Kul Vaibhav