I linked the video starts at 30secs
I've found the script of this episode.
The script says
"It's amazing. I mean, I really, really, seriously appreciate that."
That's what Louis says to Mike.
But to me, it doesn't sound like 'really, really'.
I can't even catch the words.
It sounds like mumbling and he has a lower voice.
Not clear to me. (I'm an English learner.)
Is he really saying " I really really seriously appreciate that."?