If your KICKR HEADWIND stops responding to your sensor or trainer, try simply refreshing the connection by holding down the power button for 3 seconds while in the desired mode (SPD or HR) and keeping the sensor or trainer close by. This will pair the sensor or trainer again, resolving any previous issues caused by de-synchronization.
Note: KICKR HEADWIND saves only one Heart Rate Monitor and one Speed Sensor at a time (one for each mode). Speed sensors may include trainers, speed sensors, or combination sensors like the Wahoo Blue SC.