Can't import dependency with private keyword in react

Question

I want to import a dependency that use a private keyword in my react project. When I try to start it it yield me an error :

Module parse failed: Unexpected token (10:9)
File was processed with these loaders:
 * ./node_modules/source-map-loader/dist/cjs.js
You may need an additional loader to handle the result of these loaders.
| export class Client {
>   private publicApiClient: PublicApiClient;
|   private privateApiClient: PrivateApiClient;
|   private walletClient: WalletClient;

I tried a bunch of babel plugins but nothing to do. What I can do ? Because I can't modify this code as it's part of a dependency.

Thank a lot for your time.