iPhone settings claim WiFi connection but phone using LTE

Issue noticed on iOS 15.5 on iPhone 11.

This happens every day to me, I’ll be using my phone in my apartment and notice my phone is using an LTE connection. I notice because the status bar says LTE and eventually in the month I get a notification as I’m at home that I’ve used all my data for the month. As someone that works from home and never had this issue before owning an iPhone I find this shocking. I used to use 2-3 GBs of data per month and now I’m clearing my 6 GB plan.

when I go to my iPhone’s settings it says I’m connected to my home WiFi with 2 out of 3 bars of signal strength. Restarting the router has not worked. Neither has restarting my phone.

Is this a known hardware or software issue?