Because Multistar often utilizes generic OEM firmware (commonly associated with the HiSilicon chipset), specialized software tools can generate temporary "super passwords" based on the system's current timestamp.
If your DVR is not connected to a network and the date-based passwords fail, you can force the system clock to reset to factory defaults. This is done by temporarily cutting off power to the internal memory chip. Step-by-Step Hardware Clock Reset: how to reset multistar dvr password