Default settings

I've made changes to the default settings files (print, filament, printer) and forgt to rename them before saving. Is there a way to reload these default files?

I do not think you can change default settings, but what probably happened was that you now have an extra config file named default also confusing you?.
You may load this file if not already and store in a new filename if you want.
When done check the filelist that you have this setting also available and probably two default file settings also.
You may now delete the extra "default" file from list and load original defaults if wanted.