@zaskarl3 according to Sonos here you unit should connect to the dualband SSID Sky hubs provide as it supports up to WiFi6.it is also listed as supporting up to WPA3 security so should have no problem linking to the white WiFi Max hub somyou should not need to make any changes tomthe hub.
At a guess the memory location used to store the password has got corrupted which can happen with many devices. Standard process is to tell the device to forget the connection then reboot and try again checking you are not reasing a letter like I for the figure 1 or vice versa it is easily done.. in desperation a factory reset is sometimes required.
That said while Sonos make lovely speakers but they seem to leave the networking to the work experience kid and we see multiple issues in the forum. Hopefully that helps,
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65inch Sky Glass, 3 Sky Streaming Pucks, Sky Ultrafast + and Sky SR213(white Wifi Max hub) main Wifi from 3 TP-Link Deco M4 units in access point mode
