I’m not really sure what to do – I have all of the plugins disabled, have uploaded the latest version of the theme, updated to the latest WordPress… still no luck.
Please make sure that your are not zoomed in or out on your browser. You can reset it to 100% by pushing CTRL + 0 on Windows and CMD + 0 on Mac.
If that does not help, please create a temporary admin login and post it here privately.