Estimated time vs actual

Speak up!
I have a problem with opening and closing times.
I’m using kanboard to track call opening at a third-party company.

When we are going to open task, we put the start date, estimated end date and estimated time (company sla) and do not put the actual time spent.

When I end the call (with time overflowed), it does not show in the statistics the time spent automatically (Annex 1).

How can I do this automatically?