Part controls with PartType 'Page' must refer to pages of type 'CardPart' or 'ListPart'.

I have created a Main page and one sub page. Then to link sub page to main page I have created a
Type := part
Subtype := page
in main page.
Also I have added SubPageLink property, PartType := page and PagePartID := sub page ID then when I compile I got the error "Part controls with PartType 'Page' must refer to pages of type 'CardPart' or 'ListPart'."

What could be the possible issue and the resolution?