Investigated a website that was inaccessible through Google Public DNS despite appearing to work on some networks. The domain had previously been moved between DNS providers and was using a mixture of Cloudflare and another DNS service, resulting in conflicting DNS and DNSSEC configuration. Reviewed the nameserver delegation, DNS records and DNSSEC settings, corrected the configuration and removed the conflicting setup. Verified that the domain and website were resolving correctly again through public DNS services including Google 8.8.8.8.