Hi Aman
I think the issue could be on GTS side as I can see the Transfer Log for Export. The message clearly says "Customs document type cannot be determined for external document type F8". Correct me if I am wrong, I would n't be seeing the log in GTS if it has not come into GTS. First I tried pushing it manually. It did not work. Then I tried to look into some notes where I saw that we cannot push manually only for Customs Processing. Then activated BAdi and tried. Still it is not working. Something strange. I have tried most of suggestions from Forums and friends!!
Keshav Murthy