IF AND Functions coming back as False

The #N/A error you have in your LOOKUP tells me that the cell in K4 is recognised as a text. Are you able to change the formula in K4 to be as below and see if it works.

Formula:

=VALUE(Long_If)

The LOOKUP function works this way
=LOOKUP(K4, RangeToFind, ResultingRange)

What it does is, look at K4, whatever number it maybe, and try and find it within RangeToFind. Once it finds a number (or the smaller closer number), it returns the corresponding number in ResultingRange.