If you're being blocked by the WAF PM me your IP address that you were using when it happened and I can check why.
If you're using a proxy there's a good chance someone recently used that same proxy to do something bad, so that proxy IP is now being blocked on our end from accessing web sites on our servers. We're not blocking proxies or VPNs across the board for web access but there's a much higher chance they are blocked due to high use rate for malicious behavior.
We've started blocking IPs with a bad reputation or history of bad behavior from accessing our servers. In our initial implementation we're seeing a huge decrease in spam registrations\emails and hits against mod security for exploit attempts. I'm sure there is some tweaking we'll have to do and we're working on implementing a challenge option instead of an outright block for most IPs depending on the date of their last bad behavior.