Error 18.xx is a security block. Likely if you are using Opera's or any kind of shady VPNs. Use a more common browser like safari or chrome with no extensions, no adblocks, nothing tampering with the functionality of the computer / browser
Code / Range 18.xx (ERR_ACCESS_DENIED): This error indicates that the request was denied due to a Web Application Firewall (WAF), Web Access Protection (WAP), Botman rule, or configuration setting. Essentially, the request was blocked because it violated a security rule or policy.
Source:
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