When authorizing your IP  address, you may encounter the following error message:

Error adding IP -- It's not allowed to use this IP address

Two factors could cause such an issue:
  1. You are authorizing your local IP. These IPs are the ones provided internally by your router. For example, routers would typically provide 192.168.XX.XX IPs.
  2. IPv6 proxies - Currently, our dashboard can only authorize IPv4 proxies. If you have such an IP address, we recommend that you use user/pass authorization instead. See How do I authorize my proxies?

You can access sites such as https://whatismyipaddress.com/ to know the IP address provided by your ISP.