Why isn't my iMessage and FaceTime not working? It says when I try login try connecting a network and I have a network connected

for the past two days now, whenever i go into facetime or imessage, it tells me to login with my Apple ID. after doing so, it will load for a bit, and then tell me i have a network problem, and that i need to try again. i have wifi, i have internet (i can go into safari) but nothing seems to be working. please help me!!