You will need to assign clients to providers that will be performing services.

Only the clients that are assigned to providers will be visible to the provider.

Navigate to People manager - People - Provider Assignments.

Select the employee at top right

Select the new button at top right

Select the client to assign to this provider and hit Add.

If your providers ever receive a message trying to clock in with a client that indicates they are not assigned to that client or possibly the client is missing it could be that the clients are marked as inactive. Always check that a client is active when trying to debug any situation where a provider can not clock in or add a visit/claim to that client.