Have you tried what the Ghost team suggests?
By default the ‘from’ address for mail sent from Ghost is set to the title of your publication, for example
<firstname.lastname@example.org> . To override this to something different, use:
A custom name can also optionally be provided:
"from": "'Acme Support' <email@example.com>",
Try to use a real, working email address - as this greatly improves delivery rates for important emails sent by Ghost (Like password reset requests and user invitations). If you have a company support email address, this is a good place to use it.
Taken from here: Configuration - Adapt your publication to suit your needs