The bug

It appears the prepaid_card_redeemed_minecraft values for the statistics API https://api.mojang.com/orders/statistics are not updated anymore since at least December 2020. Since then the total value remained at 4,782,079.
It is unlikely that no one has redeemed a gift card since then.

Reproduction steps

See also https://wiki.vg/Mojang_API#Statistics

Send a POST request to https://api.mojang.com/orders/statistics with the following JSON body

{
    "metricKeys": [
        "prepaid_card_redeemed_minecraft"
    ]
}

The total value of the response is 4782079 and the last24h value is 0