Countless near death experiences wherein people are declared clinically dead and testify that they found themselves above their own bodies and watched staff take action to save their lives... noting the individuals present, what was said, procedures done, and even what responders wore... testifies that consciousness continues on after death. You're essentially calling all of these people liars.
You are also testifying against Scripture which clearly teaches that life goes on after death. Even Samuel was able to be aroused from His rest and consciously prophesied against Saul while disembodied.
Jesus testifies:
Luke 24:36-39 (KJV)
36 And as they thus spake, Jesus himself stood in the midst of them, and saith unto them, Peace be unto you.
37 But they were terrified and affrighted, and supposed that they had seen a spirit.
38 And he said unto them, Why are ye troubled? and why do thoughts arise in your hearts?
39 Behold my hands and my feet, that it is I myself: handle me, and see; for a spirit hath not flesh and bones, as ye see me have.
Here the disciples were terrified, afraid that they were seeing Christ's "spirit" (ghost). Yet Jesus testifies that spirits don't have flesh and blood. They are disembodied realities.
Soul sleep is a doctrine of devils.