D-Link ZCH 510 Siren - SHM- Battery Drain 2-3 days


I am using D-Link ZCH 510 Siren with Smart things / Xiaomi Sensors.

It works fine when connected to AC power. I have got the BL-5C battery and now the alarm is put on the wall powered by the battery. In 2-3 days the battery drains and the device goes offline.

have anyone experience this and have a suggestion to overcome this issue.?