Map input freezes in Map View but Ribbon and Inspector still work

Hi there

New Mac user here but long time Windows user.

My maps keep freezing so I can't edit or add or navigate round the map branches.

However I can still use the inspector functions, change views and add topics from the ribbon etc.- but still not edit them once they're on the main map view.

I can switch to outline view and see some of the map topics.

I can switch to schedule view and navigate and add topics but then not edit them back in map view.

Any idea what might be going on?

I'm using a new MacBook Air.

Many thanks

Roger