Two remote computers with same network condition got different connection with my laptop

I have A, B computer in a local network. Their IPs are both started with 172.16.24.xxx. That means they are under the same network condition. That is all I know.
I have a laptop at home. The laptop connected to a router, and the router connected to an ISP moden.
A—laptop is direct connection.
B—laptop is also direction connection.
But sudo zerotier-cli peers shows differently.
On A, running sudo zerotier-cli peers shows
my_laptop_ID 1.12.2 LEAF 7 DIRECT 23 517 117.147.xxx.xxx/24853
117.147.xxx.xxx seems to be my ISP public IP. Located in China.
On B, running sudo zerotier-cli peers shows
my_laptop_ID1.12.2 LEAF 595 DIRECT 20 21 fd7a:115c:a1e0:ab12:4843:cd96:xxxx:xxxx/9993
However, fd7a:115c:a1e0:ab12:4843:cd96:xxxx:xxxx is located in USA!!! That is weird!!
On my laptop, ping ip of A, I got <10ms, very fast. However, ping ip of B, I got >450ms, very slow, and why zerotier still treat this connection as direct?

Can someone help me? What is wrong with zerotier? How to make connect B—laptop as fast as A—laptop?

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