WAN3 (U5G Max) identifies as wrong ISP

I just noticed that WAN3 from my U5G Max is showing the wrong ISP name. If I look at the U5G, it correctly shows that I have a T-Mobile SIM installed and am connected. If I look at the dashboard though, or check the Internet tab, it shows as "AT&T Wireless".

I did, briefly, have an AT&T SIM installed when I first got this thing, but it hasn't been there for months because there's basically no AT&T service at my home (it kept latching on to a useless -120 5G signal instead of a barely usable -110 LTE).

https://imgur.com/a/b6K8Rlv

Any idea how I can get this to identify correctly? Do I need to remove the U5G Max from my network and then add it back?

Software Versions:

• U5G Max - 7.4.1
• UCG Fiber - 5.1.12
• Network - 10.4.57