Cloudflare continues to get blocked by Endpoint Small Business. Cloudflare needs to be able to access the site so that it can create pages in its network to distribute.

I don't see how to whitelist their ips.

According to their tech support:

Can you verify that you have our IPs whitelisted on your server and at your web host? The site showing as offline generally indicates that our connections are being blocked or rate limited.

IPv4

     204.93.240.0/24 (204.93.240.0 - 204.93.240.255)
     204.93.177.0/24 (204.93.177.0 - 204.93.177.255)
     199.27.128.0/21 (199.27.128.0 - 199.27.135.255)
     173.245.48.0/20 (173.245.48.0 - 173.245.63.255)
     103.22.200.0/22 (103.22.200.0 - 103.22.203.255)
     141.101.64.0/18  (141.101.64.1 - 141.101.127.254)
     108.162.192.0/18 (108.162.192.1 - 108.162.255.254)
     190.93.240.0/20 (190.93.240.1 - 190.93.255.254)

IPv6

     2400:CB00:/32 (2400:CB00:0000:0000 - 2400:CB00:FFFF:FFFF)
     2606:4700::/32 (2606:4700:0000:0000 - 2606::4700:FFFF:FFFF)
     2803:F800::/32 (2803:F800:0000:0000 - 2803:F800:FFFF:FFFF)

What exactly is the Symantec Endpoint Protection  output indicating? Why does it say the IPs are blocked? That could be part of the issue here -- you'd want to whitelist/allow our IPs.