remove non-existent space in front of text in excel

i have these rows of cells with white spaces in front of each

e.g.

suppose cell A1 has this number "2300". for some reason there seems to be this space in front of "2300" so that it becomes " 2300"
when i clicked on the cell to erase it, it didn't seem to recognize the space...

i cant seem to lose this and when i run the vlookup formula, the formula just didnt work coz of the friggin non-existent space.

how to overcome this?

My apologies for confusing you all.

so i have 2 sheets in a workbook. one sheet (sheet1) contains the following 2 columns:

column a -- old code
column b -- new code

sheet2 contains 3 columns:

column a -- old code
column b -- date
column c -- customer

what im trying to do is to add a new code (column d) in sheet2...

i am using the vlookup formulas to get the new code but for some reason, the formula doesnt work. i am 100% sure i got the right formula.

vlookup(old code,data source,2,FALSE)

what is wrong here?

when i run the formula, it gives me #N/A