Hi and Welcome. My Name is ***** ***** I look forward to assisting you today with your question.
First we can reset your iPhone and see if it works or not. Press and hold down the Power button and Home button at the same time until it shows the Apple logo. When you see the Apple logo, release the buttons and let it boot
Then go to Settings > General > Reset and tap Reset Network Settings. This will not delete anything from your iPhone. It just resets some settings like WiFi, bluetooth etc.
Then go to Settings tap WiFi. You will find your WiFi network there. Tap it and enter your WiFi password ***** connect.
Please let me know if that didn't work, so we can continue troubleshooting
Do you have any computer there connected to your WiFi network ?
Does it connect to other WiFi networks ?
Have you tried resetting all settings ? Go to Settings > General > Reset > Reset All Settings
When you connect it to other WiFi networks, is it still showing incorrect password ?
It will reset home screen layout, bluetooth, WiFi, wallapper, ringtone etc. It will not delete any of your files or app data. Just basic settings.
You may need to go through some initial setup after resetting all settings.
If it still not working, then go to Settings > WiFi. Tap Other. Enter your SSID for Name
Select WPA or WPA2 as Security. Enter password ***** connect. Does it connect this way ?
Your network name
Enter it exactly
It is your WiFi's name. Check your other devices and you will see the network name on them (the connected one)
To make sure, your iPhone is not connecting any other WiFi network. Right ?
Is there any issue with the touch screen ?
Open Notes app. Type something and are you able to type correctly ?
It is possible that the issue is related to the WiFi chip or an issue with iOS software. To rule out iOS glitch, you have to restore it from iTunes on your computer. If this is related to software , then restoring the iPhone will fix it. But I've to warn you. If this is hardware related, there is a chance that the restoring will fail and your phone may brick which may render it useless. Since you already tried resetting settings, restoring is the only option left.
First download and install latest iTunes on your computer from here : https://www.apple.com/itunes/download/
Then connect the iPhone to your computer with the USB Cable.
Open iTunes application on your computer.
iTunes will recognize your iPhone. Select your iPhone in the top left (select iPhone icon)
Then in Summary section, click Backup and make sure "To this computer" is selected. Let the Backup complete. Do this backup one or 2 times.
Then click Restore button and let it restore. It will take some time to restore the iPhone .
After restoring, you will get option to restore your backup. Select Restore from iTunes backup and all your files will be restored. If this is software, then this will work.
Only in rare cases, it will fail. The reason is, the chip is integrated to internal board and when restoring, Apple tests all components of the board. This is the only option left.
I'm sorry, but this is the only option left as you have already tried resetting settings. Even Apple does the same thing when you take it in.
Restoring will replace the current iOS with a fresh one and if this is software glitch, restoring will tell. Only in rare cases it will fail.