copy and paste a canvas

Question

i have a canvas. there are some rectangles and elbow arrow connectors inside the canvas. i copy this canvas and paste it, after pasting in the new location either in the same word file or another word file, the elbow arrow connectors convert to line. they are no longer a connector. as seen in the picture, at first, when select a connector, red points appear.  

but after pasting, connectors never work and became line. when i move rectangles, lines don't move with rectangles. what should i do that after pasting canvas, connectors not change to line? help me.