Dynamic DNS not working with DuckDNS for Legacy DNS

Hi,

I try to update the IP of a legacy device using the Dynamic DNS option and a DuckDNS hostname (xyz.duckdns.org). Even though this seems to be working for a couple of hours, this setting is deactivated automatically after a certain time (typically on the next day): The DDNS switch is off the the hostname is gone. Is this a known bug?

Cheers

Lukas