I have an object and I added bones to it. It looks like this
I used automatic weights option to calculate the weights. But some of the vertices are not given a weight. When I move the first bone in pose mode it looks like this
I have tried removing parent relationship, deleting vertex groups and recalculating weights but the result is the same. I have no idea what could have caused this or how to fix it. Adding those vertices with vertex paint is not something I want to do unless it is the only choice I have so I am asking for help.