Hello! That's never fun and I understand why you might be upset, but there is a few things. You do not include any sort of evidence or your steam ID, its also very common for entities to go through maps on gmod if you aim down while dropping or spawning entiites. And why would you first drop your g36c to lose it then 200 bars? you should have noticed after dropping the first?
For all I know you could have just traded it away and made a bug report, we need more than I just dropped it and it fell through the floor.
I went to trade with someone I think there name was brad hd and he was a senior staff he didn’t collec any items and he checked the logs to prove that I had the items on me so if u need to clarify anything u could message him