I have been editing formulas within a range of cells without any issue until this.

When I go to replace this part of the formula: (WESPACdata!$M:$M=$A$2)*(WESPACdata!$L:$L=$B$2)*
with nothing (ie a blank), it returns this error even though when I manually delete it, the formula works fine:

\1

285h92.jpg

any thoughts? Am I doing something wrong?

Thanks in advance