Multiple errors on dash

Good morning.

I have a 2016 Fabia SEL and recently the car displayed ABS stability control not available, said I had 3 flat tyres and front assist wasnt available.

After taking the car to my local Skoda dealership they diagnosed the fault to a rear ABS sensor which they replaced as the car is still under warranty. Now the car is displaying the same faults as before. If I switch the car off then on again the faults clear. The car drives perfectly. 

Any ideas as to what might be causing these error to be displayed ? 

Many thanks for your replys in advance 

Paul