This could mean that there's a larger problem than just your internet connectivity. Let's say you've reset your router or if your internet's working normally at home and all of your other applications are able to connect to the internet just fine. Now what?
It could be that the Discord server you and your friends are using is having connectivity issues itself.
The easiest way to solve this is to use a more reliable server that isn't experiencing time-outs.
Discord has its own "Server Discovery" bar, but they're reserved for more popular games and titles. If you hit the green magnifying glass icon and type in the game you want a Discord server for, it should pop up.
But what do you do if you're playing a more niche game that doesn't pop up in "Discovery"?
You've got a couple of options.
You could either create your own server, or use a variety of different sites that list popular and reliable servers that don't show up in the app's built-in "Discovery" feature. Discord.me is a pretty great third-party site that should help you find what you're looking for.
If you wanted to go and make your own, it's actually not as daunting as it sounds, and HowToGeek has created a pretty comprehensive guide on how to do that — you can check it out right here.