Contact Form Submissions take 30 minutes to arrive when submitted via iphone

I just launched a new website for a client using the Enfold theme. We’ve been able to find resolutions for any issues via the threads on the support platform except this one. When someone submits a Get A Quote form from their iphone, it takes 30 minutes to arrive to the client’s email. Their industry is highly competitive and they try to respond to requests immediately. A 30 minute delay is way too long. Is this something that has been addressed before? To test it, you can go to the homepage on an iphone, click the get a quote button and submit the form.

Thanks for your help.