Indoor Training effect wildly inaccurate

Hi,

Just completed a training where my training effect is just plain wrong. I did the 20 min mountaintop intervals (2x 20 min ftp with 5 min rest in between), which is a pretty hard effort (imho at least) and it only registered recovery... Had the NEO 2T, extra powermeter and HR monitor connected. I did also run Zwift alongside it (ANT+, only connected to cadence, power and hrm), but let the 1040 handle the controls and recorded separately.

Really would like this to work...