can't create a new document

My Protools 11.1.3 doesn't work, as I can't open a new document, unexpectedly.

This is the message:



Could not create a new document because Assertion in "/Volumes/Development/126373/ProTools/DFW/MacBuild/../Views/UMenu.MacOS.mm", line 1547.



Could someone help me to understand what it means and what I have to do?

Many thanks in advance.