The integration was not correctly installed or it was incomplete.
Contact synchronization was not yet finished at the time of the call or SMS.
The contact was created recently, and you made a call immediately:
With the option to create new leads activated: A new lead will be created and the activity will appear there.
With the option to create new leads deactivated: The activity will appear in the next synchronization.
The contact number was recently edited or changed:
The activity will not appear until the next synchronization.
If you have some other ´problems with your CRM integrations, you can check this article
If none of the cases mentioned above is appropriate to your specific case, you can contact the support team via chat or email firstname.lastname@example.org