Tried adding new map provider, running into issues.

Topics: Bugs, Help
Feb 8 at 2:37 PM
I tried adding a new map provider (GeoPortail, see below)
And it seems to be working for the most part, except that sometimes when i zoom in it does not grab the imagery. I have to switch map type and switch back before it starts grabbing again.
I am not sure if I did something wrong.
  string MakeTileImageUrl(GPoint pos, int zoom, string language)
  {
     // http://m3.mapserver.mapy.cz/ophoto-m/14-8802-5528
     // https://wxs.ign.fr/an7nvfzojv5wa96dsga5nk8w/geoportail/wmts?layer=ORTHOIMAGERY.ORTHOPHOTOS&style=normal&tilematrixset=PM&Service=WMTS&Request=GetTile&Version=1.0.0&Format=image%2Fjpeg&TileMatrix=19&TileCol=264884&TileRow=187337

     return string.Format(UrlFormat, zoom, pos.Y, pos.X);
  }

  static readonly string UrlFormat = "https://wxs.ign.fr/an7nvfzojv5wa96dsga5nk8w/geoportail/wmts?layer=ORTHOIMAGERY.ORTHOPHOTOS&style=normal&tilematrixset=PM&Service=WMTS&Request=GetTile&Version=1.0.0&Format=image%2Fjpeg&TileMatrix={0}&TileCol={2}&TileRow={1}";