Me and a friend have ping issues with just roblox

For some reason, roblox seems to see the only app where my internet doesnt work as it should. I am brazilian, and i normally play with a group of people, where me and a friend are the only ones who have connection issues, with our ping going above 2k out of nowhere, and consistently at the same time. This have occoured for about 2 months and nearly made me stop playing the game. Somebody knows what could improve it?