SSL pinning not working in iOS

Using the above mentioned HTTP native plugin. SSL pinning is not working in iOS but works fine in Android.
As per the documentation i have placed the certificate in www/certificates folder, But It always returns success even if the certificates are not placed in folder.

My code :

      await this.http.setSSLCertMode('pinned')
      .then((a) => {
        console.log("SSL pinning success");
      }).catch(() => {
        console.log("SSL pinning failed");
      });
  }

This code always returns “a” as NULL in iOS, But returns “OK” in Android.

Hi,
Were you able to solve it ? I am facing the same issue