Front vision sensor error

[MuskokaMavic]

Recently when flying my Mavic Pro I have to calibrate my front vision sensors with DJI assistant before each flight or I get front vision sensor error.
This does seem normal to me. Any suggestions?

 

[Mossiback]

Not normal. Could they be dirty?

 

[MuskokaMavic]

Not normal. Could they be dirty

That occurred to me. I will check and clean. Thank you

 

[MuskokaMavic]

The sensors do not appear dirty. If they had been dirty I would not have been able to successfully calibrate with DJI assistant. Still don’t know what the problem is.