Apple - MacBook Pro won't connect to Wi-Fi, with correct password. Error: "The Wi-Fi network requires a WPA2 password"
I just had the same issue. The answer I found online said to go to system preferences, then network, then click advanced and then click TCP/IP and click the Renew DHCP Lease; but I don't think that did anything.
However, instead of clicking TCP/IP, stay on the Wi-Fi page (or go back to it by clicking the tab) and click the + button to add the network. You need the network name and password, and for security I chose WPA2 personal. Apply or Click OK and that should do it. It worked for me and now I get connected automatically.
I'm betting the same SSID used a different encryption mechanism previously.
Go to System Preferences ->Networks ->Advanced and remove the SSID from "Preferred networks" by selecting and clicking "-"; Turn off "Remember networks this computer has joined"
Then reboot, go to the Wi-Fi icon in the menubar (top right of your screen), select the SSID when it comes up. Enter your password and hopefully all will be well.
If that doesn't work, please try changing the SSID on your Wi-Fi modem/router, being certain that the SSID is unique. While you're at it, upgrade to 10.14.4 since there were a few, seemingly unrelated, Wi-Fi issues corrected.
Please do share what your SSID is. I'm betting your machine has "remembered" another Wi-Fi network with the same SSID, but different encryption method.
I don't know if you've resolved your issue but this is how my problem was resolved.
I have a BT Homehub router so the settings (in "advanced" tab) allowed me to 'separate' the 2.4GHz and 5GHz channel settings which resulted in 2 SSIDs being visible on the network. The 5GHz channel was recognisable from the addition of "-5" being added to my original SSID. I connected to the 5GHz channel without any problem.
It seems my issue was an inability for my MacBook air to connect to the 2.4GHz channel.
Hope it works for you too!