When your VlookUp formula doesn’t find the item you can see with your own eyes, it may be that the data have leading, trailing or extra spaces (for example: ABC , Inc. vs. ABC, Inc.).
Use the TRIM function in a new column on your data (=TRIM(A2). Then Copy/Paste Values over the original column. Also, check that your lookup array is locked by either a named range or absolute cell references (e.g., $A$2:$F$279). Otherwise, A2:F279 becomes A3:F280 when you copy it down. Finally, if your formula is looking for exact number, use 0 or FALSE in the Range Lookup syntax field.