iPhone shows different Wi-Fi name when trying to type the password

When i long press the wifi icon at the control center in order to connect to a wifi network, and then i tap on a wifi to connect, a password screen will pop-up like usual. But it shows different wifi name (apparently that is a wifi that i have connected to like year ago). i already 'forget the network', restart the iphone, and reset the network settings, but nothing happens. it still will show the old wifi name when i want to connect to any wifi by using the method stated above. Please anyone can help me?