SuperFrost is a temporary boost function designed to rapidly bring a large batch of fresh food down to freezing temperature before it settles into normal long-term storage — if it won’t activate or cancels itself shortly after starting (F12), that’s usually a problem in the control circuit or a related sensor, not a sign anything is wrong with the freezer’s standard, ongoing freezing performance.
Because normal freezing continues unaffected, this is a lower-priority repair for most households, but it’s worth having looked at eventually — the problem can sometimes be an early indicator of a sensor issue that could affect normal temperature regulation later.