I recently received a comment that the Wide 2-Column Template that I posted would not allow users to add new labels to their blog posts. Because I made the template by making just a few minor changes to the Blogger Minima template, none of the changes related to the labels, I was very surprised that there would be problems. But sure enough, she was right. I really am not an expert with this stuff, I don't claim to be, and sometimes HTML and CSS coding just does weird things. In other words, there seems to be nothing wrong with the code, but I found a solution online that solved the problem for me. Please let me know whether or not it works for you. I apologize for this inconvenience.
Solution: On this blog, The Real Blogger Status, the author explains that sometimes the post template can become corrupted. Read his instructions for the full explanation and then read what I did:
I went to Design and then "Edit HTML" and scrolled down (or Ctrl-F to find this part) until I saw:
<b:section class='main' id='main' showaddelement='no'>
Their instructions say to Remove the part in red, Save your template (confirming that you are deleting a widget) and then Replace that line and Save it again. (Your blog posts won't be deleted.)
When I did this, I removed the part in red and saved my template, but Blogger did not actually delete it. So I simply clicked View Blog and the labels came back!
Hopefully this does not happen for everyone. Please let me know if you are having trouble. Also, please let me know if there is the same problem for my other templates. I checked them and they worked fine for me but you never know!