Why is the Conversion data not being counted even though the Contacts are getting added through the Landing Pages form?

Why is the Conversion data not being counted even though the Contacts are getting added through the Landing Pages form?

The Conversion on the Landing Pages report will be counted only if the Contacts are added through the form available within the Landing Page editor. When any external form is embedded on the Landing Pages, then the addition of contacts will be counted under Abandon.