TextKit2 : - The text inserted between the attributedText(Paragraph) doesn't inherit the attributes of existing text

I have added an custom attribute for a paragraph using the below method

textStorage.addAttribute(.customCase, value: "checkList", range: paragraphRange)

When I insert some text in between the text which contains the custom attribute, that text is not inheriting/propagating the custom attribute of existing paragraph text

Old Text : - This is a test

New Text : - This is "some new" a test

The inserted part is not getting the custom attribute of the old text, Can I know why it's happening, Is it some textKit2's behaviour.

TextKit2 : - The text inserted between the attributedText(Paragraph) doesn't inherit the attributes of existing text
 
 
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