The answer depends on a lot of variables. The longest ice retention test we conducted maintained ice for 10 days. The cooler was pre-cooled, kept inside a room-temp room, and not opened regularly. Average ice retention with frequent opening and closing the Vibe cooler is about 1-2 days.
Try unplugging the pressure release valve. Sometimes the pressure due to the difference in temperatures, and the air tight seal, can make the cooler hard to open. This is typical for all coolers like this.