Good morning, @DeeUmper ...
How large (in file size) is the *.zip file that you are trying to import into your Canvas course? Also, take a look at your course "Settings" page. If you scroll about half-way down the "Settings" page, you'll see areas for "Default due time" and "Language". Just below that, there should be a heading for "File Storage". How many megabytes (MB) does your course show? Compare that to the size of your *.zip file. If your *.zip file is larger than the "File Storage" number displayed on your "Settings" screen, my guess is that is why the file isn't fully uploading to Canvas. You'd need to speak with your school's Canvas administrator to see if they could increase the "File Storage" for that course for you. If, however, you are using the FFT (Free For Teachers) version of Canvas, then you are only allowed 500 MB of storage per course, and there's no way that I'm aware of to change that. Check out the linked PDF in this Guide which compares a paid Canvas account vs. a FFT account:
Canvas Free-for-Teacher FAQ (canvaslms.com)
I hope this will be of some help to you. Sing out if you have any questions...thanks!