Why does the left sidebar disappear?

I recently got a new theme for a new blog I’m starting. The theme is Alexified (https://www.alexallied.com/alexified).

Run into this peculiar problem. Whenever I get a page not found message (example page: https://passionforcinema.com/index.php?tag=awards1) or if I click on any of the tags (example page: https://passionforcinema.com/index.php?tag=awards)

In both above example the sidebar on the left disappears. Could someone point to what the problem could be? (the author of this theme has long given up responding to questions). Would appreciate any help. The following is the Index.php of this theme…

[long code moderated – use a pastebin service for lonmg code!]