Good evening Carly and welcome back!
Thank you for reaching out to us.
We are sorry to hear about some of your customers using Hotmail not receiving their ticket emails.
I would love to help you with this topic.
What is most likely going on, is that the ticket emails are blocked by Hotmail’s spam filters.
The very first recommendation I would have for you would be to switch from the built-in WordPress generated emails to a plugin such as: https://wordpress.org/plugins/easy-wp-smtp/
That way, your ticket emails will be sent using a SMTP server of a recognized email address.
In turn, this should decrease the number of people not receiving the tickets.
Let me know how that goes.
Best regards,
Geoff B.