Messages

[System/Configuration: History]

I just created a user group w/ the same result as you, no way to delete it. Tried to remove the group name & description but was unable to save it. I had to go into the
System/Configuration: History menu & roll it back to the previous configuration to remove the group. 

[Disable hardware checksum offloadDisable hardware TCP segmentation offloadDisable hardware large receive offload]

Have you tried the settings in the Interface/Settings menu?
Specifically; 
Disable hardware checksum offload
Disable hardware TCP segmentation offload
Disable hardware large receive offload
Don't know if it will help but worth a try.

Greelan, thank you for this. Works like a charm. :) :)

Are you sure this is your Alexa? Amazon devices are sharing your wifi w/ your neighbors starting almost a year ago. My daughter has a Echo & I was seeing unknown mac addresses on my DD Wrt router. After some research I found this out. Turns out my neighbor bought new Ring doorbells which were using my wifi resources. I blocked them which you'll need to do to keep them off your network. Program is called Amazon Sidewalk.
https://arstechnica.com/gadgets/2021/05/amazon-devices-will-soon-automatically-share-your-internet-with-neighbors/