"Can't resolve hostname" (not my server)

I was on a friend's server, when it suddenly kicked me off for no apparent reason. I tried to rejoin but it gave a "Can't resolve hostname." I asked my friend and he said it was just fine on his end? I had played for several hours directly before that, and obviously it didn't randomly change the ip on its own accord..? I asked other people in my house if maybe the wifi was down, but it was not, plus I can join any other server just fine? It may fix itself but I figured I'd ask in case it didn't. I can give more details if needed, I can't think of what to put at the moment.

Update: It indeed fixed itself, but I still do wonder what went wrong.