The ~ないでください structure is a polite way to ask or request someone not to do something. It is commonly used in formal or semi-formal contexts, and it softens prohibitions or commands.
In casual situations, ください can be dropped, leaving just the ~ないで form. While less formal, it still conveys the same meaning, though it can sound more direct or blunt depending on the context.
Adding ね to the end of the sentence can soften the tone by adding the nuance of seeking agreement. It makes the request sound more considerate or gentle.
This softening helps the speaker avoid sounding too commanding.