How to implement a label on the map with smooth movement?

Question

JavaScript

Hello colleagues! The task is to make a smooth movement of the map with a label.
I implemented everything without problems as indicated in the link:
How to use the smooth movement of the map
There was a problem - I can not pick up the label?
How to change and what to add to the code so that when moving, there is a mark everywhere in the right place.
I will be very grateful to everyone for their help. A small stupor, I can not finish it myself.