I am trying to create my first model in Blender using this tutorial (you can see the files of the model here).
In the video (04:25), when one vertex is pulled down, only some of the vertices of the ring-shaped structure are pulled down.
However, when I try to do the same, the entire ring goes down (see this video).
How can I make sure that when I pull down one of the vertices, only the adjacent vertices (not the entire ring-shaped structure) is moved down (like shown in the video)?
I am using the following Blender version:
version: 2.83.2, branch: master, commit date: 2020-07-09 05:50, hash: 239fbf7d936f, type: Release build date: 2020-07-09, 04:24:13 platform: Windows 


