RAX70 Tri-Band Router Disappearing and/or non-connecting 5Ghz. Band

[BEDPilot]

Hi everyone, Looking for some help with my RAX70 router. I have it set up for 3 bands, 2.5 and 2/5 Ghz. Different SSID's. I find that the 5 Ghz. bands disappear from time to time or if connected to a device, the device will not get on the internet or I will get a "No Internet Connection" message on my device and have to switch to either the other 5 GHz SSID or the 2.4 Ghz. This is extremely frustrating and a pain... I have this router for almost two years and latest firmware upgrade did not fix issue. Please let me know if anyone has encountered this and if there is a fix since I am ready to throw it out the window. Thank you Adolfo

[FURRYe38]

What Firmware version is currently loaded?
What is the Mfr and model# of the Internet Service Providers modem/ONT the NG router is connected too?

What devices do you have connected to the router? 

Is Smart Connect enabled or disabled? There is only 2.4Ghz and 5Ghz frequencies. 

What channels are you using? Auto? Try Auto and 48 on 5Ghz. Or try setting manual channel 1, 6 or 11 on 2.4Ghz and 40 to 48 channel on 5Ghz.
Any Wifi Neighbors near by? If so, how many?

Has a factory reset and setup from scratch been performed since last FW update?

Netgear has set up a community forum specifically for the NightHawk RAX WiFi 6 Router products:
https://community.netgear.com/t5/Nighthawk-Routers-with-WiFi-6-AX/bd-p/en-home-routers-nighthawk-wif...

Please use this link to the main forum product list to review and choose where to make your posts. 
https://community.netgear.com/t5/NETGEAR-Forum/ct-p/en-netgear

Thank you.

[BEDPilot]

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Thanks @FURRYe38 

Here are my responses: 

What Firmware version is currently loaded?  Latest Router Firmware Version V1.0.11.112

What is the Mfr and model# of the Internet Service Providers modem/ONT the NG router is connected too?  ARRIS Surf Board Model S33

What devices do you have connected to the router?  iPhone 12 Pro Max, iPad Pro, IMAC, etc.  

Is Smart Connect enabled or disabled? There is only 2.4Ghz and 5Ghz frequencies.  No, separate networks across 3 bands.

What channels are you using? Auto? Try Auto and 48 on 5Ghz. Or try setting manual channel 1, 6 or 11 on 2.4Ghz and 40 to 48 channel on 5Ghz.   Auto on 2.4 - Ch. 44 on first 5Ghz and 153 on second 5Ghz (this is the one with the issues). 
Any Wifi Neighbors near by? If so, how many?  There are others, 2.4 mostly from neighboring homes that are 200-300 ft away and only 2 other networks on 5Ghz.

Has a factory reset and setup from scratch been performed since last FW update? Yes, numerous times.

Thank you.

Adolfo

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[FURRYe38]

Same thing happens if you enable Smart Connect?