Hello Lei, We learn more and more every year about how planting depth impacts the performance of transplanted trees and evergreens. Without knowing more of your situation, I would say that your evergreen is planted too deep. If this evergreen was recently transplanted I would contact the firm that installed it and let them know of your concern. Even with a warranty that covers your plant for a period of time, if it does not recover from transplanting, you will have lost a season or two and the replacement will also take a season or two to recover, so you lose 4+years. A plant that remains in stress will not grow well and be more prone to insects and diseases, and enviornmental stress, more so as it gets older.
I hope this information helps you resolve your concern with your blue spruce.
Sincerely, Richard Hentschel