Email problem with a form

My customer is not able to receive email notifications when a form is submitted.

I use Gravity Forms for an employment application form on this page: so, my client can receive applications from prospective employees. But, my customer is not able to receive email notification when the form is submitted. The feedback is registered in WP Dashboard but not emailed to my customer.
Could it be something in the domain’s dkim policy ? that google is checking with...then the email message will be bounced. The emails are going to spam. I think they are being bounced.
Customer’s domain is is hosted with Go Daddy.
Their email server is
They are using the Barracuda email filter.
I from the inbound server that my customer may be using 0365 or some hosted version of Exchange.
This is the inbound server address that we have in the Barracuda ESS filter

Also, I changed the send to email to my gmail account and everything worked. So, maybe my STMP settings are off?