I am having a similar issue with TBC Classic Server, Remulos. I managed to login now but it’s high latency (4200ms). Something is definitely wrong. either with the servers or the connections in between.
We have received similar reports from other players in this region and this appears to be some kind of routing problem happening in the area which may affect multiple ISPs. Some players have had lucking using a free VPN which can route around the problem. In the mean time, the best thing to do would be to contact your ISP to have them investigate the problem from their side.