It is not directly possible to have a fast flashing text.
One way is to visualize a Boolean in a control-component like described here: https://www.vigo6.com/how-to-display-a-blinking-message-for-a-variable/

Another way is to have a qBool in the Dynamic Variables section of your view, and then toggle this every time then Paint() Method in executed. This Boolean then determine whether to show the text or not. The blink-frequency is though out of your control, and will depend on how often the view is redrawn (how often visualized data changes)

Paint() method override example:

IF My_qBool
  THEN
    My_qBool:= FALSE
  ELSE
    My_qBool:= TRUE


FOR Viewlist_index:= 0 TO NoOfChildren-1
  DO
    IF Viewlist_index = Label_to_flash
    THEN
      IF My_qBool
      THEN 
        Call_viewlist_paint(ViewListIndex:= Viewlist_index)
    ELSE
      Call_viewlist_paint(ViewListIndex:= Viewlist_index)