It´s something wrong here. We use aircon almost everyday in our living room at 24 degrees. Around 5-7 hours a day. Night time we use aircons in two bedrooms at 22 degree for all night every night. On at 21.00 and off at about 05.00 in the morning. Besides that we have always on (24/7/365) Water dispenser machine for both hot and cold water, freezebox, refrigerator with bif freezer section, 3 computers, printer, 3 routers. TV is on for about 6-10 hours a day as well as charging 6 mobile phones, running washing machine and so on. Never using more than 600-800 units and the bill is between 3200 - 4000 bath.
In your case you probably have something that has gone bad or broke and running up the bill as it uses more electric than it should.