Hi Simon,
The provided account doesn't work, as I can see from frontend, it seems that you add class suffix for this banner incorrectly.
You can change:
hidden-xs,hidden-phone
to:
d-none d-sm-block
These classes will help to hide this module on extra small screen only. For more info about hiding elements, kindly check full list of classes here: https://getbootstrap.com/docs/5.0/utilities/display/#hiding-elements
P/s: Remember to add a space before the d-none class