When inserting or copying a slide from the template the triggers to move to the next slide multiplies on each slide

Hi, I have noticed today, that when I import additional slides from our templates, or I copy existing slide in the project, the jump to next slide when timeline starts.  If I leave them there, it just flicks right through the project, so I have had to right click on the trigger line and disconnect the link. 

the triggers don't show up under triggers menu to delete. I have not had this problem until today, is there a setting I need to change, or rebuild the template or something else I am doing wrong?