The ancient return was exposed by his sister's live stream.

Chen Hao traveled back 10,000 years to ancient times, served as the tutor of the First Emperor, wrote poems under the pseudonym Li Bai, drank wine with the Queen Mother of the West, and personally sealed away the ferocious beasts from the Classic of Mountains and Seas.
On his first day back in the modern world, he wanted to keep a low profile.
As a result, he was filmed face-to-face in his younger sister's live stream—
"Bro! You pinned that dragon down with one hand?! And you still say you're not an immortal?!"
Chen Hao: ...That's a snake, a big one.
Millions of viewers in the live stream: ??? You call this a snake???
The younger sister continued her spiel: "Brother, where did the Queen Mother of the West hide her elixir of immortality?"
Chen Hao: ...She's my friend, so it's normal for me to know her location.
The entire internet is in an uproar: Friends??? Making friends with a mythological figure???
When Chen Hao accidentally revealed an ancient secret, the whole world went crazy—
President of Country M: Mr. Chen, does Atlantis really exist?
Japanese Prime Minister: Did Xu Fu actually go to Japan?
Vatican: Where are the fragments of Noah's Ark?
Chen Hao looked at the screen full of messages and sighed:
"I just want to live a quiet, uneventful life, but you all insist on asking me these questions..."
"Alright, let's talk about it then."