If your firm is not using MFA or the o365 OAuth synchronization you must update Amicus with your new password when your exchange password has changed.
To update your password in Amicus by CARET:
1. Access Preferences -> Links -> Email -> Configure -> Step One
2. On the Test Connection window type in your new Exchange\Email password
3. Select Test Connection
Do the same for Preferences -> Links -> Calendar and Contacts -> Configure -> Step One
Please see this link if the test connection fails.