when I create a new item the drop down appear empty, but if I modify one and want to create a new one the form appears with the previous information in the drop down and a text disable
Sorry, I'm not getting your question or issue. Is the cascading dropdown is not clearing?
I believe these videos help you with Single and Multi-Select cascading dropdown functionality.
Thanks, StalinBlog - Learn To Illuminate BlogYouTube - Learn To Illuminate Videos
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