I am trying to add up all the amounts entered on several Excel sheets for specific clients.

To do this, I have several lists (spread over several sheets) with the name of each client entered in a cell (knowing that there is not only the name in this cell but also other information) and the amount in the adjacent cell (on the right).

Also complicated, the customer can appear several times on a sheet.

The idea would be to make a macro that asks for the name of the customer, adds up all the adjacent amounts and writes them on a sheet (or returns them directly in a pop-up).

Thanks in advance for your help!