Unfortunately, I have lost the power supply unit. My attempt to use a universal power supply unit backfired (https://www.galaxus.ch/de/s1/product/goobay-9-v-24-v-universal-netzteil-universalladegeraet-12459536?supplier=7241454). Does anyone have any idea where I can get a power supply unit? Or can someone tell me the output mA and V? I can't find this information in the instructions or on the internet