Can't access flutter.dev (Mac OS)

I just solved this problem using this command:

• Go to /etc/resolver folder
• Remove file called dev
• done

Which was generated by puma-dev. When I deleted it, it just worked.

Reference: https://support.google.com/chrome/thread/2228098?hl=en

Open Network Utility on your Mac, and select the Traceroute tab. Type Flutter.dev in the top empty box, then select Trace. If the first trace entry shows 127.0.0.1, you likely have proxy software, like POW, redirecting that path internally.

The Network Utility is not in System Preferences > Network.
Use Spotlight search to find the Network Utility.