Although I have connected to VHF, the default ATC in MSFS still doesn’t work! Help! At the beginning, before take off, the ATC was performed well. However, after take off, it keeps telling me to reset transponder since my transponder appears inoperative or malfunctioning!!! Even though I have reset the squawk as required, it still doesn’t work! After a while, the ATC told me that IFR was cancelled and transitioning to Charlie airspace!!! And then, I couldn’t press anything in the ATC box and there is no options provided in the ATC box as well!!