There is a missing corner in the northwest of my house and a stairwell in the northwest. How should I solve this problem?

Northwest position:

The hexagram stem represents heaven and the fathers in the family. It belongs to metal and is commonly known as Shoushan. It governs nobility, prosperity and longevity. The wind from the northwest is biting with ice. If the mountain is not high and solid, it will not block the wind and rain, and will not relieve the cold air, which is not good for vitality and the development of the family. Therefore, the preferred location in the northwest must be high and must not be sunken, and there must be no roads, rivers, or murderous intrusions. If the northwest is affected or the house is missing corners, it is advisable to place objects of the Pig zodiac sign to replenish the energy of the northwest. That is, there is a piggy bank near the northwest corner. Put a few coins in the piggy bank.