Solution: (Not sure if temporary or permanent fix)
1- goto Settings > WiFi settings
2- long-press on Connection
3- Select "Modify network config"
4- check the "Show advanced options" tick.
5- select proxy settings to Manual
6- proxy host name , input the value from 192.168.1.1 to 192.168.1.225
7- Proxy port = input one of them "8080" , "3128" , "80"
8- press the "Save".
9- turn wifi off and the On, you will not see the message ""Sign into Wi-Fi network"
10-now repeat the steps from 1 ~ 4
11- and revert back the proxy settings to "None", its Done.
12- you will be fine with this network.
Credits to XDA forum. Di ko nalang lalagay yung link, baka bawal hehehe. Sana makatulong