Rollup UMD Module Reference to Named Imports is Undefined

Question

I had a published component library (my-components) that had a specific component (Compare) in it, along w/ other components and utilities that were used in a main application. We use rollup and create several different output formats, one of which is UMD (required by one of the teams using my-components).

The component (Compare) was starting to become large, so it was moved out on its own. The rollup build was based off of what was used for my-components. After moving it out to its own repository to be built as its own component, it now had a dependency on my-components. When used in the main application (CRA app), everything works as expected. However, when the team who uses the UMD module tried to use the Compare app, they started to get errors:

Cannot read properties of undefined (reading someService)

The code in Compare is:

import {someService, somethingElse} from 'my-components';
. . .
someService.doSomething();

I saw the following warning during the build:

WARNING: { code: 'MISSING_GLOBAL_NAME', guess: 'myComponents', message: 'No name was provided for external module \'my-components\' in output.globals - guessing \'myComponents\'' }

So I explicitly added a global entry for it.

When I looked at the resulting code in the UMD module, the code looked like:

myComponents.someService.doSomething();

Why doesn't myComponents.someService resolve to the class that is exported from my-components?

My rollup.config.js looks like:

const EXTENSIONS = ['.ts', '.tsx', '.js', '.jsx', '.json'];
const umdGlobals = {
    axios: 'axios',
    lodash: '_',
    react: 'React',
    'react-dom': 'ReactDOM',
    'my-components': 'myComponents'
};

export default [
    {
        input: 'src/components/index.js',
        output: [
            { file: pkg.module, format: 'esm', sourcemap: true },
            { file: pkg.main, format: 'cjs', sourcemap: true },
            { file: pkg.umd, name: 'Compare', format: 'umd', sourcemap: true, globals: umdGlobals }
        ],
        plugins: [
            autoExternal(), 
            resolve({ extensions: EXTENSIONS, preferBuiltins: false, browser: true}),
            commonjs({include: ['node_modules/**']),
            babel({
                babelHelpers: 'bundled',
                babelrc: false,
                presets: ['@babel/preset-env', '@babel/preset-react', '@babel/preset-typescript'],
                plugins: ['@babel/plugin-transform-arrow-functions', '@babel/plugin-proposal-object-rest-spread', '@babel/plugin-proposal-class-properties],
                extensions: EXTENSIONS,
                exclude: 'node_modules/**'
            }),
            json(),
            requireContext(),
            internal(['classnames', 'pluralize'])
        ]

    }
];

I tried to put my-components inside of internal(), and remove it from the global list, but that started to give other warnings that I think were the result of a dependency inside of it, and would throw errors when the bundle was used anyway.

Any advice on what I may be missing? Is there something wrong w/ the output from the my-components that I should be trying to fix in its rollup config, or is there something I can do in my rollup config for Compare?

Any help is greatly appreciated.