Are you using the Simple Entry Tool or the Speedy Entry Tool?

There are several ways to enter a unison.

Here are two of them:

In the Simple Entry Tool:

Enter the first note.

While the first note is selected, go to

Simple menu > Simple Edit Commands > Add Interval > Unison

You can even have a keyboard shortcut.

In the Speedy Entry Tool:

Enter the first note.

Position the crosshair on the first note, but on the next scale step.

Speedy menu > Speedy Edit Commands > Add Note

Now you have a second.

To change it to a unison, position the crosshair on the “wrong” note, and drag it vertically.

It is working! Thanks a lot!!