THREE.js MIME Javascript module

I am getting this error when trying to load my three.js page live.
In my html I have specified module as my type:

<script type="module" src="./sketch.js"></script>

ERROR:

Failed to load module script: Expected a JavaScript module script but the server responded with a MIME type of “text/html”. Strict MIME type checking is enforced for module scripts per HTML spec.

This is my folder structure. I have the three.js package folder called “three.js-master”
enter image description here

Thank you for your help.