Start at the DB board: what a trip is actually telling you
There is one safe DIY step: unplug everything on the affected circuit, reset the breaker, and reintroduce appliances one at a time. If the breaker holds until a specific device goes back in, you have found your culprit. If it snaps back instantly with nothing plugged in, or you notice a burning smell or a breaker that feels warm, stop resetting it and book a professional. Repeatedly forcing a breaker that wants to trip is how melted DB buswork happens.
UAE boards have a few local quirks worth knowing before trouble starts. Water heaters usually have their own switches, sometimes on the board and sometimes on the bathroom wall, and each split AC unit typically has a dedicated isolator. Older flats often carry a second small board for the heaters alone. Ten minutes spent flipping breakers one by one and writing what each controls on the board's door turns your next fault call from a vague description into a precise one, and shortens the electrician's paid diagnosis time accordingly.