Sync problem on mac

I use iPhone,iPad and Mac on the same WiFi,and i cant sync to ankiweb suddenly.
So i use the proxy,and it works on my iphone and ipad.However the desktop version still report an error:

Connection timed out. Please try again. If you see frequent timeouts, please try a different network connection.

Error details: ⁨error sending request for url () error trying to connect: operation timed out

i have tried to open ankiweb.net on Chrome,it could really reach.So i tried to ping ankiweb.net on terminal,it seemed to report packet loss.
what can i do to fix this problem? Thanks in advance.

Please see Syncing failed: Connection timed out errors when syncing - Frequently Asked Questions