Iris Lee

Gave up and bought a Roland instead

I hope someone can help me. I live in Papua New Guinea as an expat. I have a Celviano at home. I bought a Privia PX 730 here which had been on display for almost 5 years. I bought it 7 mos ago and it worked just fine until last. One key has become lower than the others akthiugh it still produces a sound... just a little tinnier. What could be the possible reasons?