Hi,
This is my engine collision settings, in Trace Channels I have defined InteractTrace, which should be set to ECC_GameTraceChannel2 in c++.
make sure that ECC_GameTraceChannel2 is really your InteractTrace (I remember that I used a custom channel in C++ and it was not the trace channel I expected it to be, which I eventually found out after letting the object block one collision channel after another and seeing which channel in C++ is which).