The formula that you paste may have an incorrect cell reference (or references) if the formula that you copied is similar to the following example
=SUM($B$1:B3)
and you paste the formula to the left of the original location of the
formula.
Excel always creates a cell range reference in a top-left to
bottom-right fashion. For example, if the formula is in cell C4 and you
copy and paste it to cell B4, because the first cell reference in the
range uses absolute referencing ($B$1), it does not change. But, the
second cell reference in the range uses relative referencing (B3) and performs updates according to the relative location of the destination cell (in this example it should change to A3 because the pasted cell is one cell to the left of the copied cell). In this example, because of the referencing in the original formula, the copied formula has to be:
=SUM($B$1:A3)
This behavior runs contrary (top-right to bottom-left) to the way Excel creates range references in a formula, so it is automatically changed to
=SUM(A$1:$B3)
which lists the range in the default top-left to bottom-right fashion.
NOTE: The cell range is correct, but the absolute references are
incorrect.