It happened about few years back when I was still in primary school. My mother and I rented a room in a 4-room flat, whom the lanlord is an Ah Mah. She had a maid.
One night the Ah Mah and her maid went out for dinner, my mother and another friend (she also rented her own room) were in their rooms while I was in the living room. Few minutes after the Ah Mah was out, my mom and I clearly remembered her room was still lit (she didn’t close her door). Suddenly the phone in her room started ringing. I wanted to answer the phone but my mom told me it’s invading other’s privacy going into their room without permission. Of course, I didn’t go in. Seconds later, the phone stopped ringing and a voice was heard, “Hello?” The other person’s room door was opened too so all 3 of us heard the voice, we were then freaked out.