What is the significance of the grave opening when people asked Allah for help instead of Muhammad (PBUH)?

i have seen PROPHET MUHAMMAD (PBUH) IN MY DREAM .. I WAS NEAR HIS GRAVE AND FEW PEOPLE WERE SITTING BESIDE THE GREAVE .. THEY WERE SAYING “PLEASE PROPHET MUHAMMAD (PBUH) HELP US HELP US HELP US” I SAID TO THESE PEOPLE WHY ARE U SAYING FOR HELP TO PROPHET MUHAMMAD (PBUH) WHY NOT ALMIGHTY ALLAH …. SUDDENLY THEY THEN SAID HELP US ALMIGHTY ALLAH… AND WHEN THEY SAID “HELP US ALLAH” INSTEAD “MUHAMMAD” (PBUH) THE GRAVE OPENED AND PROPHET PBUH CAME OUT AND I MY SELF SAY PROPHET MUHAMMAD PBUH … BUT WHEN THE PEOPLE WERE DEMANDING HELP FROM PROPHET MUHAMMAD PBUH NOTHING WAS HAPPENING AND WHEN I TOLD THEM TO DEMAND HELP FROM ALLAH THE GRAVE OPENED AND MUHMMAD PBUH CAME OUT…… NOW I DONT UNDERSTAND THIS DREAM….. and i want you to interpret this dream from start for me .and also that there is hadith wchich says “when you watch me in dream MUHMMAD PBUH SAYS it is true because sheetan cannot come in my face”