Do I need to change my wire?
I am guessing you are in the Philippines, in a postwar development with Euro-style 220V/neutral power. 

12 square mm is not a common Euro wire size.  Philippines use American Wire Gauge so "12mm" is actually 12 AWG. This is too small for your job.  You need 10 AWG. 

The early electrifications were done to the American standard of 120/240VAC split phase.  In newer areas, they use the more efficient 220VAC single phase, still 60Hz, which allows sourcing appliances from nearby neighbors.  However AWG remained the standard for wire size. In America, NEC allows 20 amps on 12 AWG, and 30 amps on 10 AWG.