A TimThumb error has occured

The following error(s) occured:

The remote file is not a valid image. Mimetype = ''/data/c/6/c6e5773a-05b5-4d54-a36a-f24a087ade5f/gramofoto.sk/web/wp-content/plugins/photoblocks-grid-gallery/public/cache/timthumb33LFWJ

Query String : zc=4&max=1600&src=http://gramofoto.sk/wp-content/uploads/2019/01/album_PL_105-683x1024.jpg
TimThumb version : PhotoBlocks