Here are four reasons why your prayers might not be effective

1: A selfish purpose in your prayer stops the power of your prayer.

You ask and don't have because you ask with evil intentions, to waste it on your own cravings.
— James 4:3

2: Our own sins separate us from the power of prayer.

Listen to me, you who look for righteousness, you who seek the Lord:
Look to the rock from which you were cut
     and to the quarry where you were dug.
Look to Abraham your ancestor,
     and to Sarah, who gave you birth.
They were alone when I called them, but I blessed them
     and made them many.
— Isaiah 51:1-2

3: Prayer is ineffective when we do not love God totally and completely in our hearts.

Human one, suppose a land sins against me by acting faithlessly, so that I use my power against it, break off its food supply, let famine run rampant, and eliminate both humans and animals.
— Ezekiel 14:13

4: Not helping the poor and not promoting God as the center of creation.

Those who close their ears to the cries of the poor will themselves call out but receive no answer.
— Proverbs 21:13
Jesus knew their thoughts, so he said to the man with the withered hand, "Get up and stand in front of everyone." He got up and stood there.
— Luke 6:8