Singer Younha revealed that she's been having trouble sleeping.

On August 2nd, Younha tweeted, "Sleep please.. I really want to sleep, but I can't," expressing frustration about her insomnia at 4AM in the morning.

It's speculated that she could not fall asleep because she was nervous about her upcoming stage on 'I Am a Singer 2'.

Younha is said to have joined the cast of 'I Am A Singer 2' after various meetings with 'I Am a Singer' producer,�Kim Young Hee. There were rumors that she was so interested in casting Younha that she visited the star during her radio program, 'Younha's�Starry Night'.

Meanwhile, Younha is scheduled to record for 'I Am A Singer 2' at�MBC's Ilsan Dream Center within a few days.

Source & Photo: TV Daily via Nate