To start off this long winded explanation of a problem I will say I have a 2018 Samsung QN55Q6FNA QLED TV that performed all functions as expected until I upgraded my router/modem.
I was previously using Optimum's Modem Arris TM1602 and Optimum's Router Sagemcom F@st 5260CV and all services were working fine on my TV. I upgraded to the brand new Netgear Nighthawk CAX80 and when I connected my TV to the network, TV Plus stopped working. All channels appear in the channel guide and are selectable but when I select a channel it does not load and instead provides an error message "Error. There was a problem while trying to play the TV PLUS channel. Check your network settings or try again later." I must specify ALL other internet connected apps have been working as usual (Netflix, Hulu, Amazon Video, etc.), only TV Plus is encountering this issue.
In terms of troubleshooting, I've tried everything I could think of including: Upgrading Firmware (current T-KTM2AKUC-1294.1, BT-S), resetting network connection, using wired connection, using wireless connection (only 2 feet away from router), auto scanning channels again, turning off IPv6, power cycling TV, unplugging/plugging back in TV, signing in/out of Samsung Account, Resetting Smart Hub and ultimately doing a factory reset. However, I did try connecting the TV to my phone, using my phone as a hotspot and boom! TV Plus started working again. Then, I connect it back to the router and TV Plus goes offline again.
These steps led me to believe for sure it is a router issue somehow blocking access to TV Plus. That is until I remembered I have a 2016 Samsung UN43KU6300 that I rarely use for streaming purposes. I figured let me give TV Plus a shot on the older TV. Using the same wireless connection, to my surprise, TV Plus started working on my 2016 TV, running on software version 1242. A quick note about that 2016 TV is that it had been acting up ever since my house was struck by lightning (2018) while it was powered on, frying the main board. I had managed to obtain a new main board, pop the covers off and replace the fried board to successfully revive the TV but still things sometimes act up a bit. Besides the point, my thought now is that the newer software version 1294 is somehow not compatible with my router in terms of TV Plus but the older version is. Is there a way I can downgrade my 2018 TV's version to match the 2016 TV, flash drive side loading perhaps?
It is also worth noting my old modem Arris TM1602 was using the DOCSIS3.0 protocol while the new router/modem combo uses the DOCSIS3.1 protocol.
I have been in contact with Samsung Experts who have taken remote control of the TV and after 50+ minutes came up with the conclusion that it must be the Modem/Router causing the issue (since it worked on my mobile hotspot) and redirected me to my Modem/Router Supplier. I then contacted Netgear Experts to tell them everything I had learned only for them to tell me it must be a TV issue (since the 2016 TV connected) and they redirected me back to Samsung. I fear I will be in this Ping Pong of deflections for eternity which is why I came to this message board.
If anyone has any knowledge or information please share. I am an engineer and a perfectionist and it's eating away at me not knowing the solution to this problem! Thank you all who have read this far!
This may sound weird but have you tired moving the router further away from the tv and see if that helps. You mentioned that the router is positioned only 2 feet away and that may actually be an issue. It's worth a shot.