Generally speaking, the mainframe is managed by the manager, and the manager's authority is the biggest. In your case, according to my suggestion, one more work site will be added, and then the manager will set the cashier's authority. Then the cashier can operate the system at the work site the same as at the mainframe, which can solve many problems you have now. This is also the introduction of how to manage the restaurant pos machine summarized by my long-term work.