Readings 3x high on Tacx desktop App

Want to use my F5 to record my HR and to record training as an indoor cycle however all the readings in the app are two/three times what they are on my watch. It pairs really well but when my watch say 50bpm the tacx software reads 150+. I read somewhere you need to make sure you are running the latest FW on your F5 but checking in Garmin Express the only update was a GPS one which I ran successfully.

Any help would be apprecaited