Lg g3 stock calendar single event sharing problem

[bndfst]

Hi - in the stock calendar app I used the menu option to share a single event. Unfortunately i shared using Messaging instead of Google Messenger (my chosen system default) & i ticked off Messaging as my default sharing app to use in the future. Now when i try to share a single event i get an error "cannot compose message. Messaging is not your default messaging app.".

Yes i know that but try as i might i cannot find a way to select my default sharing app again in Calendar 4.40.16

Please help !