SkyQ box will not come on unless switched off at the wall and back the batteries have been changed i

[Karen03]

SkyQ box will not turn on unless it's switched off at the mains and back on the batteries have been changed in the remote as well. 

[Chodley]

does pressing the button with the orange light in it on the actual box make it come on?

if so you'll have to re-pair the remote

https://www.sky.com/help/articles/fix-remote