Sansung Side By Side water just hooked up but will not dispense

I just hooked up the water line that worked fine for my Kenmore side by side refrigerator to my Samsung. The fittings are exactly the same yet it will not dispense enough water to fill the tray and will not come out the water dispenser at all. Am I supposed to wait? I followed the directions to test the water level and it was very low. It worked great for the Kenmore. Any Ideas?