Trainer wont calibrate with TT bike

I have used my tacx flow smart trainer for over a year with a road bike and no issues at all. Recently, just bought a tt bike (canyon speedmax cf) but the trainer won’t calibrate with that new bike, saying always “too loose” and as soon as I put my old road bike, the calibration works perfectly. 

I tried checking the pressure and it’s the same on both bikes and honestly can’t find a reason why is this happening. 

anybody has an idea of what could be going on?