I just started using Blender and started a little project. I made a model and the bones myself. I used the automatic weight when parenting the armature and the model.
When I moved the legs in pose mode, the middle body bent so I thought I will just go weight painting and make some adjustments. But the model is mostly grey in weight paint mode. The bones are grey also when selected. Just a tiny bit of color is visible near the selected bone.
I tested with a cube and it worked well. I have been trying to find a similar case from the internet but have not seen one. Thank you for the help.