One of my tutorials was canceled so I switched into another one on the previous Thursday and thought I was good. Turns out I forgot to click the 'verify changes' button and my modification was never applied. So now I'm not in my tutorial for econ and they start next week.

I can no longer make any modifications to my term 1 courses on SOLAR and I'm not sure what to do. I'm going to talk to someone at the school tomorrow but I just don't know who?

I don't think my professor would be able to do anything, do you know which department I would contact/ has access to SOLAR?

You should contact your prof. It's beyond the deadline to make changes yourself via SOLAR, so section changes are now done at the discretion of the prof.
The exception to this is if there is an instructional assistant for the course, in which case you should contact them.
If the prof has someone else dealing with administrative stuff, he/she will direct you to that person.

How did that even happen? Usually SOLAR won't allow you to add a course unless you have registered in all required components (i.e. core (lecture) & tutorials or labs as a course requires).

Turns out that the course doesn't have a tutorial. I was under the impression that ever course had to have one. Sorry about that