Wireless network connection problems are observed in some of Android devices using Android 6 and prior versions. Occasionally these devices display there is an established wireless connection on the screen but when you try to connect to the Internet, they fail. This problem is originated from a bug in the operating system. The bug cause Android devices to continue to use DHCP-leased IP addresses after the leases expire, and cause Android devices to resume using IP addresses from expired DHCP leases. When you face the the same problem please disable your Wi-Fi connection and enable it again.