Changed domain on Homeassistant config now getting invalid trusted certificate

So trying to up my game and took the plunge on purchasing a domain name and rerouting all my traffic to my HA instance via my new domain. However now have some issues since it appears some devices don’t like the certificate.

Old HA external address
//xxxxxx.duckdns.

New HA external address
://HA.xxxxxxx.

Using the “Swag” docker container I updated the Homeassistant port and sub domain and domain names.

After rebooting all I can access from external address from my friends pc that has never accessed my HA instance at duckdns. But any device like my phone or laptops I get this error

Ha iOS app
“Unknown error: URLSessionTask failed with error: the certificate for this server is invalid. You might be connecting to a server that is pretending to be “ha.xxxxxxx.”which could put your confidential information at risk.”

Chrome or safari i get the warning :no_entry: proceed at your own risk warning. Then I get to the homeassistant login page and enter my credentials and it loads then says “unable to connect to Home Assistant” rety

When looking at the certificate that it can’t validate it says the certificate is listed to
xxxxxx.duckdns.

Don’t know where to go from here to fix.