TypeScript error during method overriding: Overriding vs Overloading

I have 2 classes I am using as services in angular 9: class A and class B, class B extends A

class A{
exportToCSV(data: any[], headers: any[]){
....
}

}


class B extends A{
exportToCSV(data: any[], headers: any[], metadata : any){
....
}

}


It throws this error:

Property 'exportToCSV' in type 'B' is not assignable to the same property in base type 'A'. Type '(data: any[], headers: any[], metadata : any) => void' is not assignable to type '(data: any[], headers: any[]) => void'.ts(2416)
​

Based on the documents https://www.typescriptlang.org/docs/handbook/classes.html

this should work, but it doesn't. If I make the metadata optional however, it works (https://medium.com/@kevinkreuzer/typescript-method-overloading-c256dd63245a).

I am trying to override the method but instead it's overloading the method. Can someone explain why this is happening ?

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