There are several sources that can cause your drone to not recognise or communicate with the controller once it is bound properly to the receiver.
First thing to check is that your receiver is wired to the flight controller properly (red wire to 5v, black to ground and yellow to the appropriate uart rx/signal pad). Next, check that the receiver is getting proper power (use a volt meter to measure the power going into the rx). Some receivers will power up with under rated or unstable voltage but won't send the commands to the flight controller reliably. Make sure that the receiver settings are done properly in betaflight, in the ports tab, the correct uart needs to be set to serial rx in order for the fc to recognise the rc signal based on which pad you used to connect the receiver signal wire. Lastly, In the receiver tab of betaflight, the correct rc protocol needs to be selected (sbus, dsmx, crsf etc).
If everything is done properly and all your hardware is functioning then you should see your stick and switch movements in the receiver tab of betaflight. Don't forget to verify your modes tabs and switches are set correctly it the modes tab. If you continue to have issues, please contact us for further assistance.