It might be easier with vlookup. Try this:
=IFERROR(VLOOKUP(D2,G:H,2,0),"")
The IFERROR() is for no matches, so that it throws "" in such cases.
VLOOKUP's first parameter is the value to 'look for' in the reference table, which is column G and H.
VLOOKUP will thus look for D2 in column G and return the value in the column index 2 (column G has column index 1, H will have column index 2), meaning that the value from column H will be returned.
The last parameter is 0 (or equivalently FALSE) to mean an exact match. That's what you need as opposed to approximate match.