Confirmation e-mail sent by appointment+

Hello Support Team,

Another question from me about the appointments+ plugin. I have tested the booking function but I can't receive the confirmation e-mails (as customer,as admin and as service provider)

Could you please tell me which e-mail address is used as a sender? Is it the one defined by default in the wordpress administrator panel?

If anything specific needs to be defined for this function to work, please guide me through the different steps.
Thank you for your support