Editing the code in the text editor sometimes breaks the VamTam editor. What we recommend you to do in cases like this is to remove code starting from the top until you reach a state that works. Then add the missing elements with the help of the Vamtam Drag & Drop editor (Guide to VamTam Drag and Drop Builder / Visual Composer) Alternatively you can rebuild the page but this is better option for small pages.

In general we don't recommend you to use the text editor unless you are comfortable with coding.