Hi Yarloo,
This is not a bug within the Daily Objectives feature. In order to complete this objective, you must collect $2,000,000 in-game cash from a Diamond, Black Diamond
or Gold Plated Printer. Special printers that generate more money per second won't count as you must collect from one of the named printers.
You are, however, always welcome to suggest changes to this system by creating a suggestion topic in the Server Issues/Suggestions section, you can find the template
here >.