Lizzy’s Radio is the pilot of NumberFanagram. It was known about for a while and the episode was announced in 2019, but it was later lost in time and we do not know anything about it, it was not released for four years, and most likely cancelled. The thing we know is this photo, Amethystar, Lizzy the Tiger, and Tiberadog appearing in the episode smashing the radio.
However, the latest update of NFG says it will be later updated in Season 2.