Hi all. New to ebikes and have now been riding my carrera crossfire for a few months. Apart from struggling to get the battery pack on and off I have very much enjoyed the experience. However, this week I have had an error message 04 and no power. The battery is fully charged and I have taken it on and off several times but no joy. It looks like it might be something to do with the control panel. I’ve booked a free check with Halfords but if there is an easy fix would love to avoid having to get the bike over there!