I can't add email accounts to Apple Mail on Mojave.

I set up my mid-2012 MacBook Air with a new SSD drive and reinstalled macOS Mojave from scratch. Then I was able to migrate data from the old drive to the new one. My email accounts and everything work just fine, but my wife's email accounts didn't work. They wouldn't connect, and when I tried to use her passwords, the accounts wouldn't login. I even removed the accounts and tried to reconnect to them, but Gmail and Yahoo fail to verify with the correct passwords. She can connect to her gmail and yahoo with webmail just fine, but can't set up the same accounts in Mail. What the heck is going on? Never saw this problem before. I even reinstalled Mojave. No joy.