Fixed the error and managed to identify the source of the error. The documentation insisted on import { ChartModule } from '@syncfusion/ej2-ng-charts';.
I changed the line of code into `import { ChartModule } from '@syncfusion/ej2-angular-charts';` instead.
However, if I were to use other chart services in syncfusion, I would have to import by using this import { ChartModule } from '@syncfusion/ej2-ng-charts'; which will make the project itself be unable to be compiled at all.