Unable to Download Blocked HTTP .Wav File

In the console there’s an error that reads:

Mixed Content: The site at ‘https://humdrum.theux.gallery/’ was loaded over a secure connection, but the file at ‘https://humdrum.theux.gallery/wp-content/uploads/cfdb7_uploads/1627509065-file-919-hum-in-tune-with-you-6.wav’ was redirected through an insecure connection. This file should be served over HTTPS. This download has been blocked. See https://blog.chromium.org/2020/02/protecting-users-from-insecure.html for more details.

How is the file not served over HTTPS?

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