How do I create an interface model of a map using typescript

I have a field in a Firestore collection that looks like this:
urls: map
-- 0: map
----type: string
----value: string
-- 1: map
----type: string
----value: string

Since upgrading to Typescript 4.4 the compiler is complaining, "No index signature with a parameter of type 'string' was found on type"

The model looks like this:
export interface URLS {
     urls?:  {
          type?: string;
          value?: string;
     };
}

How do I change the interface model so that the compiler understands that urls is a map?