White V2 bulbs stopped working over LAN control

I have many Yeelight bulbs in my house, all controlled by Domoticz. This has always worked perfectly!
Since last week however, two of my white V2 bulbs stopped responding to the commands from Domoticz. I could still control them by the Yeelight app, but not through LAN control.
I then replaced them with new white bulbs, and everything works perfectly again. Firmware is the same.
I already tried resetting the lamps by turning them on and off 5 times, but this didn’t help.

Could you maybe tell me what happened or how I can solve it?

Thank you!

I have the exact same issue on my v1 colour bulb. It sometimes works but usaly it dosen’t. Have had the bulb for over a year and has worked perfecly before. Hope they fix tis issue.