I see that those 2 clients were last seen this morning. If you made that change after that I would reset the wireless network connections on those clients and give the dashboard some time to reflect those changes.
Korey, that is incorrect. I have been troubleshooting this same thing & finally got confirmation. The "Channel Width" column on the client page is displaying the client's capabilities, not what they are actually connected at. This is bad design on the part of the meraki dashboard.
For example, I'm using a single RF Profile that is applied to all of my AP's. The RF Profile designates 40MHz wide channels for 5GHz. If you look at my wireless clients, most of them say 802.11ac capable and 80MHz wide channels.
I submitted a feature request for this to be changed.