Being born again does not mean "sinless." Nowhere does Jesus indicate that.
Being made sinless is what Jesus preaches, and it is what born again means. It means repenting of your sins and being washed clean.
Hebrews 10:10 and by that will, we have been made holy through the sacrifice of the body of Jesus Christ once for all.
Hebrews 10:14 because by one sacrifice he has made perfect forever those who are being made holy
Hebrews 11:40 since God had planned something better for us so that only together with us would they be made perfect.
Hebrews 12:13 And so Jesus also suffered outside the city gate to make the people holy through his own blood.
Hebrews 12:23 to the church of the firstborn, whose names are written in heaven. You have come to God, the Judge of all, to the spirits of the righteous made perfect,
Hebrews 2:11 Both the one who makes people holy and those who are made holy are of the same family. So Jesus is not ashamed to call them brothers and sisters.
John 17:19 John 17:19 For them I sanctify myself, that they too may be truly sanctified
Ephesians 5:26 to make her holy, cleansing her by the washing with water through the word,