Issue with Yeelight bulb ; Thermal shutdown ?

Hi Yeelight,
I have 9 Yeelight bulb (Color) already 2 years, and it worked great.
(schedule, Automation, Voice Commands)
4 are installed in the Entryway as group,
4 are installed in the living room as group, and one in the bedroom.

Recently one bulb start to behieve different than the others:
When it on with full power, it turn OFF by itself for few minutes and later turn ON by itself for few minutes, again and again.
When it on 30% light, everything is ok, no issue. No issue also when it for example on ON with 1% blue light.

Automation work fine ; Voice commands works fine ; the bulb itself is online

For sure it not reach 20,000 hours of work yet.
Is it Thermal shutdown mechanism ???
Is there any way to fix it ?