draw custome box

I want to create a tool in cTrader using cAlgo and Plugin that allows the user to get all the information of that section by drawing a box on the chart. including the number of candles, Pips and....
But when drawing the box chart, it moves and it is not possible to draw the box.
How cTrader box drawing tool itself, when drawing the box, the chart becomes motionless and the box can be drawn easily.
When the user wants to draw a box with my custom tool; The chart moves and the drawing box is not possible.
Feel free to guide me