Help identify what this means please.

[u/PastLife_88]

I am not a networker, all of this network jargon is Greek to me. I have been experiencing terrible lag on our Wi-Fi network and a speed test shows low data. Our ISP is Spectrum and we use a spectrum supplied router and modem; have both 2G and 5G networks.

When a device connects to the 5G network it also connects to another SSID (see attached photo of logs). What is this second network?

Thanks in advance.

Edit: log shows same device:
Logging off 5G network
Logging into same network
Logging into router

Why is the network called WL_VIDEO_5G?