I have an amount showing up in my other income, and I have no idea what it's from. I assume it came when I imported from the CRA, but I can't find it anywhere.

what line number? 104 or 130? See detailed summary on the Bottom line tax summaries page.

Other income is used to report taxable income that has not been or should not be reported anywhere else on the return. There are a lot of things that might fall into “Other Income”. You would have to figure out where it is coming from to be able to fix it. The CRA website has more details: https://www.canada.ca/en/revenue-agency/services/tax/individuals/topics/about-your-tax-return/tax-re...