RE: Rescheduling a follow-up call
Hi Ladga,
You can either create an On Demand workflow or a flow that will execute when you go to the Flow menu. If you use Flow you do the When a record is selected trigger.
When the Workflow or Flow execute, it will read all the data from the current record. You then create another Step or Action to create another record (which will be another Phone record).
You set the values of the new record based on the values of the old record, except for the Statuses and the dates.
This should be easy enough, and you can always run it on your existing flows.
If you want, you can add logic to check the the Status of the current record is Completed.
Hope this helps