NC19 Apps page not responding

I have a fresh installed NC 19 on FreeNas, and the apps page never loads, it give only 504 error.
Nginx and php log gives nothing. Nextcloud log seems saying that the appstore can’t be reached, and there is a timeout when curl the appstore. I knew appstore is hard to reach from my network. But is there some way to bypass this? Simplly manual install apps will be just fine.

{"reqId":"ne4Z3c6Hqwv9Xp0gJAxp","level":2,"time":"2020-07-27T02:34:42+00:00","remoteAddr":"","user":"ncadmin","app":"appstoreFetcher","method":"GET","url":"/settings/apps","message":"Could not connect to appstore: cURL error 28: Operation timed out after 60003 milliseconds with 638986 bytes received (see","userAgent":"Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/84.0.4147.89 Safari/537.36","version":""}