You can edit custom credentials from the All and My Credentials tabs.
You cannot edit shared credentials from the All and Shared With Me tabs.
To edit a credential:
Go to Credentials and select either the All or My Credentials tab.
Find the credential you want to edit, then select the three-dot menu.
Select Edit.
You can update the Password only. Then, select Save.
The Server checks the password against the local system or Active Directory account. If valid, the credential updates in the system. If invalid, an error message appears.
Once the password is successfully updated, workflows and schedules will use the new password.