This is the text (if you need help).
A professor gave a two-hour online lecture but didn't know he was on mute. The microphone on his iPad was switched off. This meant none of the students in his class could hear him. His university switched his classes online to reduce the spread of COVID-19. His lecture started well but then the screen on his iPad froze. The video came back but the mic was off. The professor did not notice. It might be because he used an iPad and not a computer.
Students tried to contact their professor many times but could not get through to him. They waved their arms and called his phone. The moment the professor understood his mic was off is now viral on the Internet. He looked shocked and stressed. He was upset because he wasted two hours of his students' time. He will redo the lecture at a different time. One of his students wrote: "He teaches well. I feel bad for him."
Back to the online lecture lesson.