Custom "font" doesnt work

i tried to make it but it doesnt show me it
here is the font file in font folder
    "providers": [
        {
            "type": "bitmap",
            "file": "tmpr:font/amethyst_bundle.png",
            "ascent": 2,
            "height": 16,
            "chars": [
                "\uE001"
            ]
        }
    ]
}```
the image is 16x16