If you find that your smartphone still cannot connect to Wi-Fi, follow a few simple steps.
Restart your smartphone and router. First of all, try restarting your phone.
Check the Wi-Fi settings on your smartphone. Find the section with Wi-Fi in “Settings” on your phone and make sure this feature is enabled. There is also a possibility that your device is connected to Bluetooth or another Wi-Fi network.
Check Wi-Fi password and signal. Pay attention to whether you entered the password correctly and if it is too far from the router.
Delete the Wi-Fi network and reconnect. Do this via Settings on your smartphone.
Check your router settings. Check for time limits or MAC address filters that may prevent your smartphone from connecting to Wi-Fi. You can also reset everything to factory settings and re-set all parameters.
update your software. Check for software updates on your smartphone and install them.
Contact your ISP. List all previous actions you took to fix the problem and describe the problem itself.
Check for IP Address Conflicts. Change the connection type on your phone from dynamic to static. This can be done via “Settings” in the section about Wi-Fi. Find your Wi-Fi network, click on it and then select “Change network”/”Advanced”, replace the IP address with a static one and enter a new IP address that will not conflict with other devices on the network.
Check for router updates. Make sure you have the latest router software.
Test your smartphone using other Wi-Fi networks. To do this, connect to Wi-Fi elsewhere and check if everything is working.
Source: Ferra

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