Ios storyboard error 4.25

Hi everyone,
so I am using 4.25 in mac for ios when using the storyboard for ios I get an error in lunching :

Error: ERROR: System.ArgumentOutOfRangeException: Index was out of range. Must be non-negative and less than the size of the collection.

and I went through the doc for the storyboard exactly (( what I notice the when lunching UN4 duplicate the file for the storyboard twice ))

thank you