why I can not copy a web block to a new screen flow ?

Every time I try to do it I receive this message
what does the "here" say?

probably you have a corrupt webblock and it will fail every time.
if it's easy to recreate the webblock, do that.

I did a workaround. I created a new empty web block and copied the old inside the new one. Interesting... even copying this corrupted webblock inside the same screen flow throws error.

Thanks J