Show Sanskrit letters inside Phaser.Text field

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I am struggling to make Phaser text field show special characters like these:

    [
        {"str":"ā","codeValue":257,"analog":"-a", "analogCodes": [45, 97]},
        {"str":"ī","codeValue":299,"analog":"-i", "analogCodes": [45, 105]},
        {"str":"ū","codeValue":363,"analog":"-u", "analogCodes": [45, 117]},
        {"str":"ṛ","codeValue":7771,"analog":"r.", "analogCodes": [114, 46]},
        {"str":"ṝ","codeValue":7773,"analog":"-r.", "analogCodes": [45, 114, 46]},
        {"str":"ḷ","codeValue":7735,"analog":"l.", "analogCodes": [108, 46]},
        {"str":"ḹ","codeValue":7737,"analog":"-l.", "analogCodes": [45, 108, 46]},
        {"str":"ṁ","codeValue":7745,"analog":".m", "analogCodes": [46, 109]},
        {"str":"ṃ","codeValue":7747,"analog":"m.", "analogCodes": [109, 46]},
        {"str":"ḥ","codeValue":7717,"analog":"h.", "analogCodes": [104, 46]},
        {"str":"ñ","codeValue":241,"analog":"~n", "analogCodes": [126, 110]},
        {"str":"ṅ","codeValue":7749,"analog":".n", "analogCodes": [46, 110]},
        {"str":"ṭ","codeValue":7789,"analog":"t.", "analogCodes": [116, 46]},
        {"str":"ḍ","codeValue":7693,"analog":"d.", "analogCodes": [100, 46]},
        {"str":"ṇ","codeValue":7751,"analog":"n.", "analogCodes": [110, 46]},
        {"str":"ś","codeValue":347,"analog":"'s", "analogCodes": [39, 115]},
        {"str":"ṣ","codeValue":7779,"analog":"s.", "analogCodes": [115, 46]}
    ]

People call them Sanskrit:IAST letters, romanic version for letters from Devanagari alphabet.

Some of them are not show at all, apart from those that are near code 256. Ones that are bigger like 7773 or such are not shown.

Which font should I use or are there some style settings I could use?