The result of processing black mesma

[J]

Let me introduce myself, a student of geodesy doing research on the mesma. Thanks for creating a mesma plug which can help a lot of people, but I have the following problem.

1. After processing using Mesma tools, the final result is dark like this picture. Even though I have followed the instructions on the website.
2. Does the number of bands in the satellite image affect the number of final members? If so, what are the conditions?

Notes:
I use sentinel data 2 level 2A with 12 bands
1 pixel plot (2x (10 x 10 m) = 20x 20 m) = 4 spectral libraries
1 Class = 30 plots
1 Class = 120 spectral libraries
3 Class = 360 spectral libraries

Please help me , thank you for your attention