Last month FR had an issue with Load Balancer (I think). Now FR is ok. I think after that error your proxy was still looking into error proxy site. Proxy kept cache and still pointing to that ip address which was cached during error. If you know how to empty log and cache content from the proxy, just clear. OR from browser delete cache for that proxy, history and download files. It will force the proxy site to clear the cache.
thanks.
i’ll PM you