Dreaming about an ambulance, it tells you that you have asked for or accepted help. It is an awareness of the fact that a solution, support is coming to you. It may feel that this is coming to you from the outside. But in reality you are the ambulance and the staff, the sick person (asking for help). So it is not literally it is a reflection of your soul that makes you become aware and / or calls for help (wake up moment) you help yourself and / or the person involved.
Another explanation is that the ambulance reflects your mental state, but also complications in situations and feelings, emotions, pent up fears that you have to learn to express or understand. Yet another possibility is a decline, burnout, stress experiences. An addition is the fear or experience of setbacks, foolishness, impetuousness in your learning process, situation and possibilities that make you feel limited.
As a very important alternative, you can of course also link a trauma experience and/or memory to it, so that these kinds of dreams and visions reflect a fearful moment and life experience. Dreams are a processing of your daily life, so if something very violent happens in your life, this can come out through your dream world. Ambulance, Police, Fire department dreams are very common here!