I have created a new custom command for the Appointment table in Dataverse, which should run JavaScript that opens a custom page in a modal. I have used the approach previously, where it has worked fine.
However, when I click the button, nothing happens.
When I open the component library from the designer I can't see the command I created - only the ones I created a long time ago.

Moreover, when I run the Command Checker in the model-driven app, it also shows the error Component was not found in the library.

Has anyone else experienced this - and perhaps found a solution or workaround?