Planned date & duration do not update

I have planed many tasks with dependencies. Once the project has been calculated, it has shifted tasks in 2024. So i try to plan them as i want.
But the planned date does not change accordingly.

For example, i have a 70 days task, which began in September. It should end in January; How to make the planned value reflect the correct planning?

Well, attached is another example.
I set the duration for a given task to 3 days, and set some workload (2h each). When click on calculator, it adjust the task duration to one day, maybe because the tool consider that resources are at 100% capacity so the duration is shorten to 1 day.
Is this the correct assomption ?

Thank you for all your replies. 

Once activites are listed and sequenced, planning an activity is partially based on calculation (activity resource requirements, resource calendars, amount of work, etc...), but also involve others factors like exper judgment, analogous estimating or previous experience. 
For example, for a given task, let's say a firewall rule setup, the workload will be only 0,5d, but the duration will be 10 day due to external factors. Thoses external factors may be diverses and variable over time (process, incident, ..). 
Other example is when you don't have full time resource -- many IT projects operate with matrix organization. You even don't have a fixed rate resource assignement, and it will perform the assigned task based on his team priority (incident generaly take precedence for example).

The tool can calculate planning based on ultiples factors as you listed, this is very helpfull. But it is alway up to the project manager to monitor and adjust workload and duration, based on real, environnemental factor and experience. 
Tis has nothing related to "wish" or "nice gantt". This is related to real project management. 

So, is there a possibilité to manually take control of this two key elements (workload and duration), letting the tool to calcultae dates, capacity planning, alerting, etc -- everything Projeqtor do very well. 

Than you