Invoice for different customers

Huh, so you mean multiple recipients of that invoice? If you send it via Dexxter, you can fill in:

"cc"

"BCC"

Fill in? Or do you mean something else?

You will have to create a new invoice each time if it has to go to other people for a new service. Because then you need other numbering on your sales invoice.

What I mean is sending the same invoice (amount, description, etc.), but of course with a different beneficiary, to different customers.

So this is not possible if I read your last paragraph correctly.