The tube with ammonia, without turning it over, was closed with a stopper, immersed in a vessel with water

The tube with ammonia, without turning it over, was closed with a stopper, immersed in a vessel with water, then the stopper was opened. Why does the water rise in the test tube?

Before immersing a test tube with ammonia in a vessel with water, the pressure in the test tube was the same as in the atmosphere. However, in the process of dissolving ammonia in water, the pressure begins to decrease, and since the atmospheric pressure did not change at this time, it acts on the water and lifts the test tube with ammonia.