vanilla js import and export in old project

Question

I am trying to clean up the js in an old project, where I cannot add things like typescript etc.

So I am trying to split up the functionality into different files, and create some order from the chaos (I currently have multiple 10k lines js files).

For example I have an index.js which is for a specific page. On that page I am trying to call a function via an onclick to call dmrLookupByType

import * as dmrService from "../../services/DMRService.js";

// function to be called from HTML
function dmrLookupByType(type){
    console.log("called dmrLookupByType function");
    dmrService.dmrLookUp(type);
}

In DMRService.js there is a single function (so far)

export function dmrLookUp(type)
    {
        console.log("reached dmrLookup in DMRService file");
        console.log("received type: ", type);
    }

The script it self is included on the page as this.

<script type="module" src='/javascripts/src/pages/applicationCreate/index.js'></script>

But i keep getting "Uncaught ReferenceError: dmrLookupByType is not defined"

I also tried wrapping dmrservice in a class to use, but that didn't really change anything either.

Any ideas what I'm doing wrong?