Hello. Are you saving your files with extensions? Take for example a json file called: ASGTemplate. If you save it as such (with a json or yaml extension): ASGTemplate.json or ASGTemplate.yaml, then the color coding should come on. However, if you've already saved the file without the extension you can still get color coding.
On the bottom right, click on the "plain text" status bar item and choose the language from the resulting options.