Help: I need a formula that counts how many cells in a range match another range

It sound simple enough, but no matter what I do it will not count how many cells in my range C2:C48, match those in my criteria E2:K33.

The cells in column C are a result of a formula (which I actually got from ChatGPT), which lists 15 minute intervals between cells A1 and B1. So i don't know if it's the fact they're a formula which is throwing off the count functions.
Ideally, I would like this tool for anyone to be able to put in a start and end time, and the formulas will count how many of those 15 minute intervals match those of the criteria.

I hope this makes sense, I've tried to make it as simple as possible.

Book1.xlsx

Simple Countif

Originally Posted by NewYears1978

Simple Countif

Thanks! But it doesn't quite work, it omits some of the results, for some reason... For example c41 appears in E31, yet that isn't being counted?

I think I've worked it out, if I use a value formula on column C - e.g. =value(C2,"HH:MM:SS") in the adjacent column, and do the same with the values in the E columns, then I can do a sumproduct(countif formula and it's counting it correctly now

I'm talking to myself here I guess lol but if anyone has a better method, please share - I'm all for learning