I get a 550 error every time I try and send an email to my zoho email address

I get a 550 error every time I try and send an email to my zoho email address

I recently switched from wordpress.com to .org and ever since I can't send or receive emails from my email account that uses my domain name. Any idea how to fix this? I just get error 550 and the message that this user no longer exists

the email address in question is jjfox@thebackpackersalmanac.com and the website is www.thebackpackersalmanac.com