If you have done everything you can and are still attacked there are only 2 explanations:
First, God wants to teach you that His grace is sufficient, as with Paul. Paul prayed 3 times to have the demon attacking him removed but God said no, He wanted Paul to learn to lean on God’s grace and see it was sufficient. Read 2 Corinthians 12:7-10.
Second, the other explanation is that He wants you to seek Him more deeply as to what is allowing these demons to continue working. There must be something they are holding on to as an opening. If there is something in your life, your thoughts, your focus, your attitude to this, etc., that needs to change God will allow them to remain in order for you to seek Him and get free from that sin in your life. Humble yourself before Him. Let Him search your life, actions, thoughts, etc., and show you whatever is sin (Psalm 139:23-24). Pray often about this, sit quietly listening to Him speak. Fasting is good as well.