Restart everything. Sometimes switching a device off then on again can fix WiFi connection problems. First restart your iPhone, then try to connect to WiFi. If WiFi's still not working, restart the router or modem, and try again.
Restart your iOS or iPadOS device. Restart your router and cable or DSL modem by unplugging the device and then plugging it back in. After you restart each device, see if you fixed the issue.
Check to make sure that your phone is connected to the correct network, and that the network's settings are correct. You may also want to try forgetting the network and reconnecting to it, as well as checking for any updates to your phone's firmware.
The most common reasons why your iPad or iPhone won't connect to Wi-Fi include a poor connection signal, an incorrect Wi-Fi password, your Wi-Fi or mobile data settings, restricted network settings, or even a bulky phone case. A weak Wi-Fi connection can also mean you need to increase your internet speed.
Check to see if your router is unplugged or if the power is cut off — your solution may be as simple as restarting your router or plugging it back in. Check if your devices are trying to connect to a different network.
Your issues with your wi-fi not working could be caused by you simply not being in the optimal range for your router. Most routers aren't designed to transmit signals through a large area, so you could be running into an issue with “digital dead zones” in your home or office.
On Android phones and tablets, you can swipe down with two fingers from the top of your screen. Depending on the make of your device, you'll see a three-wave WiFi icon, or you'll see an option called Internet. Tap on it and turn on the toggle switch next to WiFi.
No data or media are deleted. Reset Network Settings: All network settings are removed. In addition, the device name assigned in Settings > General > About is reset to “iPhone,” and manually trusted certificates (such as for websites) are changed to untrusted. Cellular data roaming may also be turned off.
Like iPhone, resetting Android network settings brings Wi-Fi, Bluetooth, VPN, and cellular connections to the original state. If you want to use them again, you need to establish them from the very beginning.
Most commonly, people reset their iPhone because they are experiencing major software errors, like issues connecting to networks or apps crashing. Resetting the phone to its factory settings should resolve these errors and restore normal functioning. It's also smart to reset your iPhone before selling it.
A no data connection error can be the result of a basic software glitch, damaged hardware, or even a system-wide outage that renders the entire mobile network unavailable.
Delete and Then Re-Add the Wi-Fi Network
Authentication issues can also cause your Android phone not to connect to a Wi-Fi network. In this case, remove your Wi-Fi network from your phone and then re-add it to the phone. You'll need your Wi-Fi network's password to perform this procedure, so keep that ready.
A reset restores your modem to its factory default settings. It will also erase any customized settings you may have changed, including static IP address setup, DNS, personalized password, WiFi settings, routing and DHCP settings.
When it comes to your iPhone and iPad, you should restart them once per week. As we said, this will help wipe the memory clean, and it might make your iPhone or iPad feel like it's working faster. You might not feel like it needs it, but the older your device gets, the more it's going to need a quick reboot.