If you you were dreaming of having the wrong key to a lock, the meaning is clear. You were trying to open a door to an opportunity, with the wrong approach. In other words, you tried your luck with something that does not suit you.
If your dream did not show you having other keys, then you have no other chances of exploring for the right key to open the lock. This usually means you have to move on and look for other doors. Different doors may be open to you.