Each part can only occur once in a given content type.
There are various options you can look at;
- If your Insight data can be described as a single string, you could implement it as a Field instead. Fields can be added as many times as needed.
- You could modify your insight part to itself hold a list of items (for instance as a comma-delimited string).
- Your insight part can perform a 1-n join with another table or content item, to hold a list of items.
Which of the above you choose depends on what data is in your part.