Wifi Adapter cant obtain ipv4 and ipv6

I use college wifi connection. I am having this issue from the past two days. I cant connect to the internet through wifi(LAN works)!! I can connect to the wifi network. But the network name contains some number at the end in my connections. (eg:- if the SSID is "router", my laptop shows it as "router 2", "router 3" etc or unidentified network..) And i cant connect to the internet!! When...