We don't know why he blocked you in the first place. Depending on the relationship/ situation that you have had with this person, they are not obligated to talk to you. Nor we are not entitled to their time. Perhaps, the blocking was their way of putting up healthy boundaries? (IMO)

It could mean that you are hoping that he would talk to you again. Dreaming about them probably means that this situation is at the forefront of your mind right now.