This error normally indicates a user is accessing the iplicit sign-in URL through a shared bookmark, often provided to newer members of staff.
Saved bookmarks are often generated with a unique consent tokens registered against an individual's device or browser, and therefore when copied and sent to a third party, these links are invalidated.
This often depends at what stage the bookmark was saved, for examples after a username and password has been entered, and therefore will not be compatible with another user's credentials.
Please try the following link to see if this is more successful https://login.iplicit.com/login/domain