Hi Joni,
Email delivery problems can arise due to multiple issues. Mostly it will be anti spam checks on the recipient server is blocking mails or sender mail server is blacklisted .
Initially, what we can do is disable anti spam methods on the domain. If you receive too many spams then enable anti spam methods and whitelist the sender email address/domains.
To know more details please contact our sales team at
sales@canadianwebhosting.com.