I using Oracle 11g and arcgis 10.4.1.
You may need to set the Oracle DB accounts to have a password that expires. Once the password expires, ArcGIS Desktop should have a pop-up that asks for a new PW. I have seen this with the SDE user before.
Here is some documentation on doing this. Usually this is handled by the DBA.
Oracle passwords - changing, expiring and locking users
Managing Security for Oracle Database Users
Retrieving data ...