How to exclude contacts in the custom object from the campaign?

Hi Team,

When a prospect submits an application, this data is stored in the custom object. We are currently running a campaign to resend promotional emails to those who were unsuccessful in the first stage, encouraging them to enroll again.

What we are trying to achieve is:

Send them the email.
After 7 days, check in the canvas if they have submitted an application in the last 7 days.
If they have, automatically exclude them from future communications.

The issue is that I don’t see an option in the canvas for the decision step “Has a contact in the custom object.”