Why this caculator doesn't work properly?
My calculator CITIZEN SR-270X worked well, but one day I pressed button “on” and it doesn't work. Then I went near the window where the light is and it started to work. Then I went where is darker and I pressed button “on" again. It doesn't work again. I tired to charge it with sun's energy but it doesn't work. My calculator is new. He is like one and half year.l old. What can be wrong? Please help me. My exams are coming
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