I bought a commercial house at home, and now I find that the threshold stone of the entrance door is lower than the ground level outside the door. What should I do? (how to remedy or resolve feng shui

I bought a commercial house at home, and now I find that the threshold stone of the entrance door is lower than the ground level outside the door. What should I do? (how to remedy or resolve feng shui? ) In principle, the floor inside the house must be higher than the walkway outside. It is easy to cause the water running in the corridor to stay in the house and the water running in the house can't get out. From the perspective of geomantic omen, the remedy: 1, raising the threshold height, the threshold is to block money. 2. Spread wooden floor or composite floor on the basis of the original indoor floor to increase the original floor height. 3. If the wooden floor is not practical, you can add a thicker foot pad at the indoor entrance, just beyond the outside.