Pdfkit freeform highlighter overlaps on text/other annotations.

Hi,
Im working on a pdf annotation app, here Im using ink annotation for highlighter, the problem is the highlighter overlaps on the annotations/text but in case of apple’s default highlighter it goes behind the elements but however limitations of default highlighter is its not freeform. How do I develop a freeform highlighter that goes behind all the pdf elements.
Pdfkit freeform highlighter overlaps on text/other annotations.
 
 
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