The Territory Engine will run only once a day UNLESS the Administrator
asks that the Territory Engine be run upon import - immediately.
Go to: Account Setup > Security > Apply Territory Engine on Create Set this to Yes!
That will force the engine to be run once a contact is added to the database either by import or web form (if its a new record and not an update). See the attachment
Alternatively, Users and user groups can always be assigned manually to the sales team of a contact or entity by using the "Add Remove Team Member" choice after doing a Search within an entity.