Can't hard reset new bulbs

Hi all,

I don't have a Hue bridge but rather a generic ZigBee dongle which connects to Home Assistant through Zigbee2MQTT.

I have a few Hue bulbs connected to this setup, and I was able to pair them fine by following a sequence I found online of turning them off for 5, on for 8, off for 2, on for 8, repeatedly and they then flash at which point they connect to my hub fine.

However, I've just purchased two bulbs, both Hue white and colour, model number 9290011420, and for the life of me I can't get them to reset. I've tried turning them on and off quicky, the reset sequence, Zigbee2MQTT's touchlink mode, etc

Any idea what the reset sequence is for these bulbs? Thanks