Source map error

I am working on the jammming project in react II ( https://www.codecademy.com/paths/full-stack-engineer-career-path/tracks/fscp-22-react-part-ii/modules/wdcp-22-jammming/kanban_projects/jammming-react18 ). I keep getting a warning “Source map error”. I don’t know what is causing it or even where to begin to look. I have written no code yet, I’ve only run create-react-app and deleted a couple of jsx components in src/app.js. does anyone have any idea what could be causing this?