The macro recorder will store the actions you take when recording the macro: since you recorded hitting Paste (or equivalently the action Edit > Paste), that is the action that will be recorded. If you want the macro to type text, then you will have to type the text instead of pasting it… then the macro will type the exact text that you typed.
If you’ve got a lot of text to type for the macro: instead of recording that long text, just type an indicator. Then save the macro, exit Notepad++, and reload Notepad++. Edit the shortcuts.xml in your AppData Notepad++ and put in the longer string(s) into the places held by the placeholder (the macro will record one typed character per action, but you can actually put longer strings there). Save shortcuts.xml and restart Notepad++, and now your macro will have the longer string rather than the shorter.