If you've recently logged a call, email, task, or meeting you may see a delay in the Last Contacted or Last Activity Date properties updating for that particular contact, company, or deal. The delay for these properties should be fairly short, but during periods of heavy traffic, could be increased. Check back later and you should see the properties have been updated accordingly.
Activities logged on a contact record will be reflected in these properties on both the contact record and the record of the associated company. The Last Contacted and Last Activity Date properties on deal records will only reflect activities logged directly on the deal and will not be impacted by activities on the associated contact and company records.
Learn how you can customize which contact, company, and deal records are associated with an activity here.