Camera View Goes Purple

I have been using Nest Cam wired outdoor for few years it isn't all the time exposed to sun but cam view went purple. Did a bit of a research and found out it could be becaue of heating of the unit.

I unplugged it and took inside let is rest for a day or two then started running it indoor after 10-15 mins it turned purple again without being exposed to sun...

Possibly, it is an hardware faliure but could be something else. Could you recommend how this can be fixed?

Thanks!