Tacx Bushido: No resistance change when in Workout mode

I’ve been having an issue recently.
I use a Tacx Bushido smart trainer. It’s firmware is up to date.
When in Workout mode, changes in watt target are not taking place. ie. Only way to reach target is pedalling very fast or changing gears -although sometimes I can’t even reach the target-.
By the way, ERG mode is reported as on.
Any suggestions?