Diablo III: Reaper of Souls

Bogota, Colombia... south america

Interesting. It could simply be distance.
You're pretty damn far away from where the servers are hosted, while connections can be bounced all over the world, it doesn't change the fact that there's still going to be some processing time between you and the server.

If they can manage to get into the game, there'll be a vertical bar on the HUD, next to your resource meter, between the orb that your mana / whatever is stored in and the settings buttons.

That'll give latency information. If your ping is absurdly high, that'd be what the issue is.