I am trying to use mapbox in our c++ application on windows.

I created new public and secret tokens at https://account.mapbox.com/access-tokens
In the above page there is a Default public token.
ONLY the Default public token is working and I am able to see the map tiles

But the newly created tokens are not working and I am getting a blank map without tiles as follows.

I am using the public and secret tokens as follows in the url and tile layer as follows:

var mapBoxUrl = 'https://api.mapbox.com/styles/v1/{id}/tiles/{z}/{x}/{y}?access_token=< *access token* >';

var mapboxTileLayer = L.tileLayer(mapBoxUrl, {
    tileSize: 512,  
    maxZoom: 25,
    zoomOffset: -1,
    attribution: 'Map data OpenStreetMap',
    id: 'mapbox/streets-v11'
});

Why the newly created public and secret tokens not working and how to resolve it?