If you have tried all the steps and your TV still refuses to update, your hardware may be obsolete. In that case, consider purchasing an external streaming stick (Fire Stick or Chromecast) and plugging it into the HDMI port. This bypasses the Nikai OS entirely, giving you modern software without needing a TV firmware update.
You're referring to the software update for Nikai TVs! Here are some potential features that might be included in a Nikai TV software update: Nikai Tv Software Update