Types of property 'cacheLocation' are incompatible

I have an old app in react with javascript, but I started a new one, to slowly migrate the .JS code to Typescript.

The first file I want to migrate its a configuration file, when its .js build succeeds.

WHen renamed to .TS I get this error

/Users/xx/yy/lulo/src/adalConfig.ts
(13,54): Argument of type '{ tenant: string; clientId: string; endpoints: { api: string; }; 'apiUrl': string; cacheLocation: string; }' is not assignable to parameter of type 'AdalConfig'.
  Types of property 'cacheLocation' are incompatible.
    Type 'string' is not assignable to type '"localStorage" | "sessionStorage" | undefined'

The file is this:

import { AuthenticationContext, adalFetch, withAdalLogin } from 'react-adal';

export const adalConfig = {
  tenant: 'xxxx-c220-48a2-a73f-1177fa2c098e',
  clientId: 'xxxxx-bd54-456d-8aa7-f8cab3147fd2',
  endpoints: {
    api:'xxxxx-abaa-4519-82cf-e9d022b87536'
  },
  'apiUrl': 'https://xxxxx-app.azurewebsites.net/api',
  cacheLocation: 'localStorage'
};

export const authContext = new AuthenticationContext(adalConfig);

export const adalApiFetch = (fetch, url, options) =>
  adalFetch(authContext, adalConfig.endpoints.api, fetch, adalConfig.apiUrl+url, options);

export const withAdalLoginApi = withAdalLogin(authContext, adalConfig.endpoints.api);

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