Mr.Children on TV

I watched a music program on TV.

The name of TV program is "FNS songs festival".

This program is broadcast live.

Of course, Mr.Children was there, and it sang 2 songs.

But the vocalist Kazutoshi Sakurai mistook the song's word.

I was surprised a bit, but sometimes he mistake his song's word on live broadcast.

I cannot understand that he's singer-song writer but he sometimes mistake.