Class not recognized in dataset in RF classification with GEE

Question

I want to classify imagery from different regions with a classifier trained in one specific region. My training and test dataset contains polygons which are assigned to 4 different classes (class 0 - class 3). I can run my classification and get some results but if I examin the classifier I created, it turns out, it only has 3 assigned classes:

I do not understand why class 1 seems to be missing. I checked my input file several times, I exported it again from GIS to be sure the asset I use contains all data I need. But still there is no class 1.

I am not sure what part of my code I should post here as my code is running fine. Also as I said, my input data is fine. Anyone maybe experienced sth. like this before and has some advise how to get all classes in my classifier?

Nevertheless, here is a link to my running script: https://code.earthengine.google.com/9541fdd845f93754d0d36e7e0c26cb44

Answer 1

The problem here was the cloud filter which led to missing imagery in some areas of my region. It seems all data of class 1 was coincidentally located in an area without imagery and therefor it was not part of the classification results. Solution for now is to remove the cloud filter. Still have to figure out now what to do with all those clouds.