Email goes to SPAM on one form, but not on another

Hi,

When I send a request from this form:
https://dreamsevents.nl/contact/kinderfeestje-aanvraag-formulier/
It goes to spam in my Gmail,

But when I send a request from this form:
https://dreamssurfschool.nl/contact/surfles-aanvragen/
I just receive it in my inbox. The settings of the forms are the same.

Does anyone have any idea what might go wrong here?

Thanks, Scott

https://www.ads-software.com/plugins/si-contact-form/