Custom UIView Part overlap each other part

[ivrylobs]

I have the problem with creating a Custom Part and when setup part it overlap with each other parts

First i have implemented CartPartView and UIButton to my Custom Part Class which is The red Dropdown in the second CartPartViewController and then i have created the second Part that had implemented the UIView with CartPartView so i setup part as the right side code below

i setup the card by red dropdown first, yellow "iOSDropDown" and Button "Show Card" so the second part overlap between first part and third part how can i fix that?