Mac keychain is reset everyday
It’s often a result of corrupted keychain files which can be fixed in three steps using Keychain Access first aid.


Open "Keychain Access” (Applications > Utilities)
Open the “Keychain Access” menu and choose “Keychain First Aid”
Enter the users password and check the “Repair” box, then click “Start”


After keychain repairs are completed, exit out of Keychain Access and reboot. You may be asked one more time for the login, but from this point on it should remember it.