Now, please note that I don’t use BPMN as often as you (so I could pick this up in the wrong way) but I think I know what’s going on. You’re referring to the “called element” option which you see in the call activity specification, right? (so: select the call activity and then click the ‘dotted button’ behind it to select another element).
I also noticed that it renames itself when you do that. Although it makes sense to me I have good news: this is fully customizable.
Right click somewhere in your diagram, a menu appears, and then find the “Presentation Options” section. In there you’ll find another sub-section called “Call Activity Display Options”. That has the option “Show called element name”, which is enabled by default. If you disable this (just click it) then your call activity will display its own name again.
I hope this helps!