Just had Hue Groups stop working for me as well.. I few days ago I switched to Indigo 2022.2 but all was good. Then suddenly tonight (2 days later) Hue devices of type 'Hue Group' just stopped working.. Similar to your issue, single bulb configurations seem fine.. Not sure if there was a Hue firmware change or something. I tried updating to the latest version of the plugin but it didn't help