Just got DDOS'd the first few times my internet worked after restarting my router, but now it's not. It's saying there's a DNS error.

What do I do? Some guys just keeps hitting me offline and the first two times I could just restart my router and it worked. Now it won't. I'm worried because I don't know how long it will last. I keep trying to restart my router, and I'll update if anything changes.

Is there anyway I can stop this?