The tracker moved from Legacy to Hardware category.
The hardware category assumes more functionality.
First of all, select this type(from Hardware category) of a device in the unit settings, then you will be offered a new server and port.
Data on old IP will come, however, new units can only be sent to new servers.
Also, you can try to point your device to the IP, not the DNS. Just push the “IP” button near DNS in the “Server Host” field.
If you have any additional questions, you can write to us at firstname.lastname@example.org