SUMIFS function returns 0 and totalling hours over 24 hours

Hi All
I run a recruitment agency and every month have to tot up hours at certain rates and based on whether they are an App booking or Non App booking.
This month, my SUMIFS function is returning 0 and i cannot work out why (H68-H70). This function works for Non App (H74-H76) but not for App and I cannot for life of me work out the problem. It is driving me nuts!!

Second query on same sheet. Ideally I would like to use line U (Hours worked) as this would be more accurate but this is formatted as time to tot up hours worked automatically. It does not seem to work at all. Is there any way I can format this line differently so it does tot up time automatically and can still be totted up according to SUMIFS rules.

Thirdly, if any of you people much cleverer than me can advise an easier way to do this overall, then I would be forever truly forever grateful, there must be a better way.

Many thanks for all your help!!

Alex