Just pulling off the vine is not getting the roots and it will still grow. Trace the vine back to the root, then pull off the trailing part. Put a paper towel roll, or make a funnel shaped tube out of cardboard. Press it into the ground over the vine root and spray with roundup. Roundup kills what it touches and is neutralized when it hits the ground and water will also neutralize it. Leave the tube there and spray the surrounding impatiens with water to wash them off, in case there was overspray. Keep the water from the hose below the tube. When the plants are dry take the tube out. Within 2 weeks the vine will be dead