Come annullare un bonifico?

Depends on what you paid for and what you bought, if via pay pal it's normal and if via bank then you have to call them and try to undo it.

If you want to cancel a current transfer, you must submit an appropriate instruction to the bank (by phone, in person or via online banking) , remembering that it must be received at least several minutes before the next Elixir session

How to undo a transfer? If you want to reverse a transfer, you'll need to contact the bank you sent the payment from. The bank has time to cancel the transfer, usually around 24 hours. If it's been longer than that, the bank can't guarantee that you can cancel the transfer, but it's worth a try. There may also be additional costs associated with canceling the transfer.

Call the bank as soon as possible.

you need to call the bank and try to undo it somehow

I refer to one of the most detailed: https://www.policja.pl/pol/aktualnosci/158350,Szkolenie-polickich-psow.html

Call the bank and say what happened why you want to undo