Email Forum Issues?

I have a website for a client who are unable to receive an email from their web form submissions. I have tested with other email address and works fine.

1 of them is a Gmail address and the other a custom one (name@example.net), doesn’t appear in junk, just doesn’t come through.

Anyone had similar problems and has a solution?

https://preview.webflow.com/preview/boomerang-printing?utm_medium=preview_link&utm_source=designer&utm_content=boomerang-printing&preview=ca3bf27a864d0348fad42922cd76463a&pageId=5e86610c4a22d9d107d25c78&workflow=preview