Formula for look up value

Dear Colleague,

Please could you help me to resolve this issue as per the file attached

Hi,

I'm not exactly sure what you're looking for, but I'll answer assuming you want to remove duplicate rows.

If you don't need a formula, you can do Data -> Remove Duplicates:

If you have the possibility to use a recent version of Excel (or Google Sheets), this can be done easily with the UNIQUE function: