APC/UPS
Not fuctioning

I have purchased APC UPS in the month of Feb Sl No. BB0648026012 and model BE500.

Complaint: 1.After pressing “ON” button green indication was not coming after few seconds Red indication comes continuously with beep sound.

2. From your end replaced with SL No. BB0725013089 approx 6months back.

3. Now once again same problem exists what should I do?