This is happening because you are using a from address that includes @olynet.com and you haven't added an spf record to your DNS server to give the mycafecommerce.com server permission to send emails for you.
Email providers are getting more strict in preventing SPAM and recently they have increased security to block emails that aren't specifically granted permission to send emails.
The solution is to add an SPF record to your DNS server and grant the mycafecommerce server the right to send emails on your behalf (or update the FROM address in your email settings in your mycafecommerce admin to use an @mycafecommerce.com email address like firstname.lastname@example.org)
To add an SPF record, you can go to your Domain Hosting provider and add a DNS type TXT record with the value:
v=spf1 a mx ip4:18.104.22.168 -all