There are two basic products on the market that are referred to as a seat belt alarm stopper. The first is simply an unattached seat belt clip that can be inserted into the receptacle. The safest way to use this option is to source a seat belt clip, or tongue, that matches your original seatbelt exactly. You can look for one at a scrap yard or parts store.  Measure the overall dimensions of the clip’s exposed metal section, as well as the dimensions of your receptor. Remember that driving without using a seatbelt is very dangerous, and against the law in most areas. The other stopper option, called an extender, is a piece that clips into the receptacle, but also provides an additional receptacle so that you can use your seat belt without removing the alarm stopper. You should purchase your extender from the original equipment manufacturer of the seat belt, and it must meet the criteria in its operating manual, including mass and stature. Following the criteria for your extender is important because your seat belt system needs to pass an anchorage pull test, which ensures that it can withstand crash-level forces. You can find these requirements online or by asking your seat belt manufacturer. Make sure that your stopper fits your seat belt receptacle. Then, simply click the stopper into your receptacle. You are now free of the dinging alarm sounds.

TL;DR in Indonesian:
Dapatkan klip sabuk pengaman lepas jika sabuk pengaman tidak ingin digunakan. Beli extender jika berencana memakai sabuk pengaman. Pasang penghenti alarm sabuk pengaman.