@Skynet, user had already asked that here:
https://theminixforum.com/index.php...fw-20200430-bugtracker.2759/page-8#post-21982
And since I could never have any of my Minix boxes to work properly at 2.4Ghz when connected to a double frequency router, even if that could be useful at times, I gave him my best suggestion, which he had obviously already tried. The U22-XJ as the U1 don't have a function similar to the U9-H to select the WiFi frequency, and so obviously this sitution is still not solved by the user... Obviously he will be posting again and again until we get him an obvious solution.
EDITED: The obvious solution is to bring the WiFi signal closer to the U22-XJ, by extending the router signal with one of those simple devices that are meant to do exctly that, and allow the box to connect to the 5GHz signal as it should.