Some shifts wont add on my staff rota weekly total

Hi, I have nearly completed my staff rota for the care home I work at and have added some extra shift times but it doesn't seem to be adding them in to the weekly total on the right hand side. Someone very kindly put in this formula for me but I cant work out why it isn't adding up (probably something very simple). The shifts are "M3 (10:00-15:00)" and YC (10:00-16:00). I would be very grateful if someone could help me with this, rota attached.

Thanks in advance

Bigtiger