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I checked the email address and found it in our bounce list, the reason is below:
Reason(s) : smtp; 550 5.7.1 Service unavailable; client [**.***.**.**] blocked using dnsbl.sorbs.net
When your email address is in our bounce list you will not receive emails until you remove the email address from our bounce list, this guide will help you with that: How-to-Remove-Your-Email-Address-from-Bounce-List
Here is a guide that will help you to set up your emails to avoid bouncing: How-to-Setup-Email-Alerts-to-Prevent-Email-Bouncing-Related-Issues
As you're using our default sender email addresses, if the issue persists then you should ask your email provider to white-list our IP addresses: Whitelisting-JotMails-IP-Addresses
Hope this helps.