RSVP confirmation email has code that should be invisible in the header

The confirmation email that a person gets after registering to an event, has a big line of code related to “schema.org”.
It’s right on top of the header so its the first thing people see when they open the email.

Can someone help me understand why this happens and how can I fix it?

Its a chunk of code that seems to scare a lot of people, and they think the email is hacking some how -.-

Example: [{“@context”:”https:\/\/schema.org”,”@type”:”EventReservation”,”reservationNumber”:52561,”reservationStatus”:”https:\/\/schema.org\/Confirmed”,”underName”:{“@type”:”Person”,”name”:”teste de email”,”email”:””},”reservationFor”:{“@type”:”Event”,”name”:””,”url”:””,”description”:””,”startDate”:””,”endDate”:””,”location”:{“@type”:”Place”,”name”:””,”address”:{“@type”:”PostalAddress”,”streetAddress”:””,”addressLocality”:””,”addressRegion”:””,”postalCode”:””,”addressCountry”:””}}},”ticketToken”:”ea3710e589″,”ticketNumber”:52561,”numSeats”:”1″}]