Adjusting an invoice

Dear Sir/Madam,

I sent an invoice but forgot to add the date of the activity. This is important for the customer. I would like to amend the original invoice and send it again. Is that possible?

An additional problem is that I also sent the invoice via Peppol. If I send the invoice a second time, do I need to cancel the first one in some other way to prevent it from being charged twice?

Best regards from a novice Dexxter user, Lotte