Jeremiah chapter 7 verse 16
Jeremiah chapter 14 verses 11 & 12
Psalm 18 verse 41
As for you, do not pray for this people, or lift up cry or prayer for them, and do not intercede with me, for I do not hear you..
The Lord said to me: “Do not pray for the welfare of this people. Though they fast, I will not hear their cry, and though they offer burnt offering and cereal offering, I will not accept them; but I will consume them by the sword, by famine, and by pestilence.
They cried for help, but there was none to save, they cried to the Lord, but he did not answer them
Bible study passage:
Jeremiah chapter 7 verses 1 - end
From the the Bible passages above, it is very clear that the Lord does not answer all prayers. The Lord answering your prayers will depend on your conduct and your behaviour even if you fast and pray for the whole day.