My smart devices won't connect to helix wifi

Not all devices connect, but some do. I'm not getting the pattern. I thought Helix Fi wasn't supporting the 2.4GHz band, but it does, as some devices can connect on that band. Others just won't detect the wi-fi network, e.g., Fitbit Versa and Sonos One. The manufacturers are clueless and will just suggest to retry, retry, retry, retry again, then RMA the device and retry. They just want us to give up, stop using their devices and reduce their customer base to the lucky owners for this their devices work. This is really bad business model, but that's what I observe, each time I have issues, and I have a lot of them, more and more, to the point I will soon need to completely shut everything down for my mental well-being.

The wi-fi issue is probably because the Helix Fi router is not fully 802.11n compliant, or client devices don't comply and the router is too strict. That reminds me of an issue I had on Mac OS X: a mouse was working well on Windows/Linux, but not detected at all by Mac OS X. The mouse driver on Mac OS X was too strict, rejecting the third-party mouse not fully complying to the standard. Apple will say this will work only with Apple mice for simplicity, but this is not true. There is little we can do as consumers, other than giving up on Helix, replacing the non-working wi-fi devices or adding a second router, with a second wi-fi network, that will just cause issues. Probably it could work if you don't use the Helix wi-fi network at all except for Helix TV terminals (or you wire the TV terminals through Ethernet and disable the Helix wi-fi altogether). I'm not getting why Videotron bundles the router with the modem, this is a really bad idea. They just focus on giving the Internet access; internal network management is up to the customer.