Odd... nothing is really blocking me... same for EU, JP and other... other currencies work, just not excavator on my nvidia. I also tested a different internet connection, in case my IP was blocked for some reason. Would nicehash block ip for just certain crypto or all??? because I am connecting to nicehash on other crypto.
I was having the same problem as you, turned out to be my router, an AC68u. I switched to DDWRT and it works fine now.