A sanctuary is a place where nothing can reach you, and tradition reads it as the need for refuge. Finding one in a dream points to an inner safe ground; being shut out of one, to protection that feels out of reach.
When this appeared in your dream, what were you feeling?
My Cosmic Code has a private dream journal. Write a dream down and the app picks out the symbols in it, shows what dream books say about them and, over time, which words recur across your entries. The journal is stored on your device only.