We understand your concern for A and their struggle with a bad attitude. Let us first remember that it is through the name of Jesus Christ that we have access to God, as it is written in John 14:6 WEB: "Jesus said to him, I am the way, the truth, and the life. No one comes to the Father, except through me." It is only by His Name and no other.
In addressing A's situation, we must remember that God works in the hearts of all people, but He also gives us the free will to choose our path. It is important to pray for A to have a willing spirit to accept God's work in their life. As it says in Psalm 51:10 WEB: "Create in me a clean heart, O God. Renew a right spirit within me."
We should pray that A will be filled with the Holy Spirit, which produces love instead of negativity which is addressed in
Ephesians 4 29-32 WEB: "Let no corrupt speech proceed out of your mouth, but such as is good for building up as the need may be, that it may give grace to those who hear. Don’t grieve the Holy Spirit of God, in whom you were sealed for the day of redemption. Let all bitterness, wrath, anger, outcry, and slander be put away from you, with all malice. And be kind to one another, tender hearted, forgiving each other, just as God also in Christ forgave you."
And that they will be kind and loving./ A Corinthians 13:4-5 WEB: "Love is patient and is kind; love doesn’t envy. Love doesn’t brag, is not proud, doesn’t behave itself inappropriately, doesn’t seek its own way, is not provoked, takes no account of the wrong,"
We must also be careful not to wish for A to be removed from our lives if they do not change. Rather, we should pray for our own patience and love towards them, as difficult as it may be. Remember Jesus' words in Matthew 5:44 WEB: "But I tell you, love your enemies, bless those who curse you, do good to those who hate you, and pray for those who mistreat you and persecute you,"
Let us pray together:
"Dear Heavenly Father, we come before You in the name of Jesus Christ, lifting up A to You. Lord, we ask that You soften A's heart and fill them with Your Holy Spirit, replacing negativity with love, patience, and kindness. Help A to see the power of their words and actions, and guide them towards a life that reflects a better attitude. Lord, we also ask for wisdom and patience for ourselves, that we may love and support A as You do. Help us to defeat our natural feeling to dislike and to remove discordant personalities, but rather to be a support that defies all human reasoning. We cast away this discord with fasting and prayer, believing in the name of Jesus Christ. We pray that A does not walk away from God, putting themselves in the category of those who have hardened their hearts to the World and its God. And in Your loving kindness, help us to remember that it is only with the name and power of the Lord Jesus Christ that all we ask is possible. In Jesus' name, we pray. Amen."