You may have the spirit of a former human whose energy manifests only at certain times of the year. Unless it becomes increasingly active, I wouldn't worry about it.
If you have access to a shop that sells burning sage, you might use that in each room and your parking garage. Sage has been used by Medicine men & women for centuries to "cleanse the energies" from places so these energies can go to the Light. Sage is inexpensive to purchase, and doesn't linger offensively in the air for very long.
Some days are DIAMONDS; some days are STONES!