Hello Patrick,
Let me describe how CRM contacts work:
-> Contacts and their activities can be seen by the contacts owners only, if you are an Agent. An agent can not see other agent’s contacts or activity.
-> Manager can see all. All the contacts event if it owns by other agents as Manager has all the rights to see all.
So, please make sure you do not have an agent role, rather, you have a CRM manager role from your user profile. Reference screenshot: https://prnt.sc/onr99a
Thanks