When using Lit Localize I get Module not found

Question

I'm trying to use the @lit/localize library. I have followed the documentation https://lit.dev/docs/localization/overview/

I've also looked at the sample application https://github.com/lit/lit/tree/main/packages/localize/examples/runtime-ts

What I'm struggling with is that when I pass a parameter for language (http://localhost:3001?locale=es-419) I get the following error

Cannot find module './es-419.js'
 at http://localhost:3001/asset-src_routable-components_UsersScreen_ts.js:54:11

What I have noticed is that if I pass the default language of "en" in the URL the screen loads fine. If i pass junk locale it will give me a different error saying invalid locale code.

It feels like for some reason my locale*.js file is not being built into the project properly. I have followed the link in the comments and tried to add the extensions. But that does not work either

module.exports = (env, argv) =>
 merge(customConfigs(env, argv), {
 resolve: {
 extensions: ['.ts', '.js'],
 }
 });

• Augustine Kim: Have you run lit-localize build? and make sure your config has the correct outdir and mode.
• Brian S: It builds without error. I have added my lit-localize.json file.
• Augustine Kim: It's hard to say without seeing the whole project. Do you see the file generate after running the build command? If so this could be webpack failing to resolve the .js extension so checkout stackoverflow.com/a/67929013/19498660
• Brian S: @AugustineKim I re-wrote the question with the issue I'm having now. I feel I'm closer, but still missing something
• Augustine Kim: There are a lot of other moving parts that are not shown here. Check the outputDir in lit-localize.json, and see if that's actually in your project directory after running. Does that path match with what you're doing in configureLocalization call? Is your dev server configured to serve those files?