Hope you didn't pay good money to the idiot who came & told you to use powder instead of tablets to cure an electronics fault. All of the symptoms you describe are electronic faults - machine not stopping unless disconnected from the wall, beeping in the night, F0 codes coming up (There is no such code programmed only F1 F2 or F3) all these point to a faulty control board. Get the PCB board replaced.
Lincoln Appliance NZ, July 2009