feature services cloned get a size of 0 KB

[JoanneTallon2]

I cloned feature service with clone_items function. Feature services cloned work perfectly but for each of them, on the item page detail, a size of 0KB is displayed. 

Url are however correct (hosted folder) and items are mentioned as hosted.

Should I be worried about this 0KB size or is it "normal"?

same results with a Portal and AGOL. 

thank you in advance