I've done the 'Enemy of my enemy' quest before, and now I want to play 'Arsenal of Oddities - Outbreak Perfected'. So I needed to get The Fallen Transponder and I did found it and picked it up, but it's not in my inventory (and postman doesn't have it) or in Triumphs.
I went to that place (two times) to pick it up again and it's not there anymore.
Please help, thanks in advance
(and sorry for bad English)