edit:
This approach can still fix the issue, note that you should also add the HTTPS_PROXY and HTTP_PROXY to $HOME/.config/systemd/user/openclaw-gateway.service:

For example:

[Service]
...
Environment="HTTP_PROXY=http://172.25.128.1:10810"
Environment="HTTPS_PROXY=http://172.25.128.1:10810"

original content:

clawdbot cannot use HTTP_PROXY and HTTPS_PROXY set in the environment variables, because the nature of the undici.

Workaround for folks who met the same issue:

Find the openclaw.mjs by running:

readlink -f "$(which openclaw)"

Then add the following code in openclaw.mjs after all import statements:

import { ProxyAgent, setGlobalDispatcher } from "undici";
const proxy =
  process.env.HTTPS_PROXY ||
  process.env.HTTP_PROXY;

if (proxy) {
  setGlobalDispatcher(new ProxyAgent(proxy));
}