The USB-C (female) adapters are hard to find due to technically being non-compliant. If you're interested about the reasons and some further context, I can recommend this article: https://hackaday.com/2022/12/27/all-about-usb-c-illegal-adapters/
In your specific case, it's twice as hard to find such an adapter due to MiniUSB being so uncommon these days.
And yet they were perfectly okay with providing the service for free while they were still busy starving off the competition. No tears for Google shall be shed here.