Can't see Anthem MRX 720

Hi I am just setting up my Anthem 720. I can control it via IP using their app but my Simple Control app does not see it on the network to connect to.
It sees every other IP device and has worked robustly otherwise

See here:

https://www.simplecontrol.com/check-compatibility/

As per the list, it is not AutoDiscovered, but the information is there to add it as controllable.