TO1254D oscilloscope does not turn on

Henry1

greetings
a few months ago I bought two TO1254D oscilloscopes, they worked fine but for a few days, one of the two stopped working, when I press the power button it sounds 3 times and the screen does not turn on, I hope you can help me,

Jing

Dear Sir，
Press the power button and the buzzer goes off three times. You can charge the machine before trying to turn it on.