Typically, when the SEO Analyzer scans only one page or no pages at all, it means it is getting blocked somehow from accessing your website.
Below you find our list of IP addresses for you to whitelist and avoid any issues or blockages:
It is also relevant to know the ports we connect:
For HTTP, we connect to 80 port.
For HTTPS to 443 by default
If you have whitelisted our IPs and the issue is still happening, refer to this article Why does the Site Audit only scan one page (or no pages) on my website?