Flux 2 power watts bouncing everywhere

Hi just received my new Flux 2 set it up upgraded the firmware & calibrated spin down on tacx app. Connected to Zwift and started a work out . I’m having problems with the power watts fluctuating up and down by quite a lot it’s very annoying ! My Tacx vortex did not do this! Am I doing something wrong in set up connection . I’m using tacx ant+ dongel connetected to pc laptop also using Halfords heart rate strap . Is anyone else having problems with the new Flux 2

I am having similar issue with Flux 2 although the resistance fluctuates so dramatically you can hardly pedal from one second to the next. Would be good if this could be looked at by Zwift asap

Could you fix the problem?