Error:Secret API keys should not be used in your app. When use X-Platform in the headers of revenueCat Get endpoint

Question

Revenue Cat docs clearly mentions that you can specify the operating system in the Get request, by specifying OS in the headers by using X-Platform property, so you can get OS specific management_url

curl --request GET \
     --url https://api.revenuecat.com/v1/subscribers/app_user_id \
     --header 'X-Platform: ios' \
     --header 'accept: application/json'

Refrence : https://www.revenuecat.com/reference/subscribers#the-subscriber-object

But when I use X-Platform in my call , it throws following error

{
  code: 7243,
  message: 'Secret API keys should not be used in your app.'
}

My API Call In NestJs

 const data = await lastValueFrom<SubscriberInfo>(
      this.httpService
        .get(`${revenueCatBaseURl}${userId}`, {
          headers: {
            'Content-Type': 'application/json',
            'X-Platform': 'ios',
            accept: 'application/json',
            Authorization: 'Bearer token,
          },
        })
        .pipe(
          map((res) => {
            return res.data;
          }),
          catchError((error: AxiosError) => {
            console.log(error.response.data);
            throw 'An error happened!';
          }),
        ),
    );

The call works fine without X-Platform