Thanks for letting me know, perhaps we can start a support group 😃
This sounds very much as if someone has gone into the TV settings menu and manually set the IP address/subnet/DNS server. If you can get to those settings and they're not on some version of "automatic" then make that setting.
*I've never in my life come across a device that had issues because the 5GHz and 2.4GHz radios had the same SSID - I've definitely come across devices that had issues being set up because they are 2.4GHz only though!
Hello,
BT have sent me a new hub and the TV has connected first time so ask for a new one!
I really struggled with 2.4 and 5 being on the same SSID, found the best thing to do was turn off 5 completely so everything works, only the mobile phone used 5 anyway