Mark 11:22 And Jesus, replying, said to them, Have faith in God [constantly].
23 Truly I tell you, whoever says to this mountain, Be lifted up and thrown into the sea! and does not doubt at all in his heart but believes that what he says will take place, it will be done for him. 24 For this reason I am telling you, whatever you ask for in prayer, believe (trust and be confident) that it is granted to you, and you will [get it]. 25 And when ye stand praying, forgive, if ye have ought against any: that your Father also which is in heaven may forgive you your trespasses. 26 But if ye do not forgive, neither will your Father which is in heaven forgive your trespasses.
Jesus said we can change our circumstances by what we say, that we can speak to the mountain (our circumstance) in our lives that needs to change. He said if we believe that what ask and what we say will happen, it will be granted to us. But first He said for it to work, if we hold anything against anyone we first have to forgive, so that our Father can forgive us.
Therefore it you’re believing and saying isn’t working, check and see where you need to love. Check with Jesus to see who you may be holding in un-forgiveness.