Proverbs 1:17 For in vain is a net spread in the sight of any bird 

A bad or negative dream is not an absolute. It is a call to action. No matter what the dream symbolizes,we have been equipped with the ability to turn the negative to positive. With the right kind of prayer and action. As soon as you wake up from a bad dream, you should cancel it.

A simple prayer like this:

“I cancel that negative dream I just had about ___ (fill in the blanks) in the
name of Jesus. I decree that it shall NOT manifest in the physical in Jesus’
name. I release the fire of God on every satanic actor in that dream. I plead
the blood of Jesus and I hold up the banner of victory in Christ Jesus. Let the
angels of the LORD go on a “search and destroy” mission in the land of the
living and of the dead … to destroy every power, spirit, personality, device, or
animal programmed to attack me in the dream. Henceforth, let no one or nothing trouble me in the dream for I bear on my body the marks of the Lord Jesus
Christ . Amen”  (Galatians 6:17)

I cancel this bad dream in the name of Jesus and I declare that tragedy and calamity
is not my lot according to the Word of God

Sources: Cracking the Dream Code by Elisha Goodman.