C422 In the Sea of Fire

Why did the door close all of a sudden?

Yiran gently walked to the door and turned the door handle. When she found that it could not move at all, she was even more surprised. She raised her hand to pat the door and shouted, " Is there anyone?"

"Director Su, this is too strange. Why can't the door be opened?" Yiran turned two more times and found that the door still could not be opened