VLook UP Restrictions

[meganday]

I- I am trying to take a part number: A2 in one tab - I want to look it up on tab 2 in colum A2 and replace it with what is in C2.

=VLOOKUP(A2,Sheet2!$A:$B,2,FALSE) is my formula, but it is returning the formula back in the cell.

I have spaces, -, :, in my number.

Are those some restrictions? Is there any way around it? Find and replace? I have 114 lines of different part numbers.