3 The signal is unstable
4 First of all, the iPhone 11 can't connect to wifi because the signal is not stable. If your phone is located far away from the router or there is an obstruction, the signal will be weak, resulting in no wifi connection. At this point, you can try to move closer to the router or place the router higher to enhance the signal.
5 Enter an incorrect password
6 Second, the Apple 11 can not connect to the wifi may also be due to the input password is wrong. When connecting to wifi, make sure you enter the correct password. If you're not sure if your password is correct, try connecting to the same wifi on another device and see if you can connect successfully.
Maybe the wifi switch on your phone didn't turn on? Or the wifi on the Popsicle, the transmitting point is far away from your phone and can't be connected. Or the signal is weak.