Customs Document Type cannot be determined for External document Type

Hello Team,

While transferring the inbound delivery to GTS, I am getting the below error "Customs Document Type cannot be determined for External Document Type EL"

I tried to implement the OSS Note # 1238850 but system is not allowing to implement.

My system has EHP 4 package level. Please help me to resolve this issue.

Thanks & Regards

Rahul