Conflicting Themes in WordPress Multisite configuration

I used Oxygen for my site builder at my multisite careerboosteruniversity.com. I have another site https://coursepro1.careerboosteruniversity.com as part of that multisite configuration, that is using CoursePro. After lots of trial and error, I discovered that my Oxygen plugin was causing the CoursePro theme not to work correctly on my https://coursepro1.careerboosteruniversity.com site. Is there a way to configure multisite’s so that each site has it’s own discrete theme configuration? There probably is, but while I am an experienced WordPress guy, I’m just learning and starting to use Multisite. Thank you in advance.

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