Since few weeks several people have talked about a malicious script they've got from a plugin or something else. It replaces the actual deposit address provided by a fake one on their screen . They said they managed to easily block the evil script with Adblock but IMO it's better to double check with another device (a smartphone or another computer). Maybe you've been victim of this malicious script.

I checked on two smartphones and this deposit address is available on all my devices. I checked this malicious script in my browser's log and it was not detected. Obviously, the money went to the fbc address, but for some reason they do not credit it to my balance. My account balance is still not credited and support continues to be unresponsive.
I am waiting for a response from the support...