It looks like the set-up of your data sheet is an absolute nightmare!
Merged cells are just about the worst invention in Excel, and most accomplished programmers will avoid them like the plague!
They are extremely difficult to work with, and cause all sorts of issues for things like sorting and VBA.
Trying to look up data from such a structure can be quite daunting. If you have the ability to change it and work from a structure that contains no merged cells, it would probably be much better.
If not, I don't think it is anything that I can help you with.