Mail Returned because No DNS Lookup

I have my Yunohost server running on a RaspberryPi at Home. The mail server works great … but I got this message from an email I sent today:

550-Your message was rejected by this system and was not delivered.
550-Reason: This system will not accept messages from servers/devices with
no reverse DNS. IP=[1**.***.***.***] 550-Protection provided by: MagicMail
version 3.0 550-For more information, please visit the URL:
550-or contact your ISP or mail server operator. 550
1d194f06-3294-11e8-a3ae-005056941aa1 (in reply to RCPT TO command)

Is there a way of getting around this?

Yes, you must set a RDNS. In fact, it’s to link one ip(yours) to a domain name. To configure it, it’s a bit more complicated : if you have a box, you can try to search for the rdns config. If there is no RDNS setting, try to contact your ISP and ask them to link your ip to your domain. it’s strange that the server you sent your email refused that…

If you have any question, don’t hesitate to ask them.