Use a Plunger: Start by using a plunger that all Singapore houses should have. Place the plunger over the drain hole and create a seal. Push down gently and then pull up sharply. Repeat this motion several times to dislodge the blockage.

Hot Water and Dish Soap: Boil a kettle of water and let it cool slightly. Add a few (or more) squirts of dish soap to the toilet bowl. Pour the hot water into the bowl from waist height. The combination of hot water and soap may help break down the blockage and/or stubborn poop.

Baking Soda and Vinegar: If the blockage persists, try pouring a cup of baking soda into the toilet bowl, followed by a cup of white vinegar. Allow the mixture to sit for a while. The chemical reaction might help dissolve the blockage. Flush the toilet after some time.

Use a Toilet Auger: If the above methods don't work, you can use a toilet auger or a drain snake which you can buy from any of the Singapore hardware stores. Insert the auger into the toilet and crank the handle to break up or pull out the blockage.