What makes a valid sensor

I tried to use yaml discovery to add sensors but snmp extend doesn’t present everything with a clean index. I added a sensor php and everything is discovered and presents the proper states.

This lasts until some hours later when the sensors get deleted. If I manually run discovery.php again the sensors are added back.

What makes a sensor invalid if a new discovery adds them just fine.

I have the same problem with always the same sensor here. Sometimes disappears/deleted and then later it comes back again with the discovery process. I also have it as YAML detected. Will do some tests with php later .

Is there a way to validate a sensor? I don’t understand why the sensor is added when I perform manual discovery but deleted when the discovery is automated.