Agenda does not let me change the keyboard mapping

What I did:
I installed a new keyboard mapping for my Bepo TypeMatrix keyboard. Within Agenda, I want to change the keyboard mapping, either by using the keyboard shortcut or by clicking on the flag icon in the menu bar.

What happened:
The keyboard mapping refuses to change and stays in French, AZERTY, my default setting

What I expected:
The keyboard mapping should change and let me use my BEPO layout.

Things that might be helpful to know (Agenda version, OS and model, etc):
I use MacOS Mojave, with last upgrades. Agenda is up to date and my computer is a MacBook Pro 15-inch, 2018.

That’s very odd. I have definitely used Agenda with other keyboards (eg Kanji) during testing. We certainly don’t do anything to deliberately block that.

Maybe worth restarting the device, and perhaps taking a look in the System Preferences keyboard settings.