After installing new router I re-started PC and looked for wireless networks: found and could connect to both 2.5G and 5G TP-Link networks (current computer doesn't have 6G but am upgrading soon).  I chose 5G on WiFi 2 channel (I have two wifi adapters).  Then I started setup via Chrome web browser and all seemed to go fine, including firmware update.  But when that setup was complete, the 5G network was no longer visible & only the 2.5 G was available for connection to the PC.  Re-booting doesn't help.  What happened?  Could it have something to do with the feature that allows the router to direct traffic through any channel (2.5/5/6) for best throughput?