So are these verses not in your bible Van?
Luk 8:13 The seeds on rocky ground are those who hear the word and receive it with joy, but they have no root. They believe for a season, but in the time of testing, they fall away.
1Ti 4:1 Now the Spirit expressly states that in later times some will abandon the faith to follow deceitful spirits and the teachings of demons,
Heb 3:12 See to it, brothers, that none of you has a wicked heart of unbelief that turns away from the living God.
No verse or passage says or suggests a person can lose their salvation, once born anew. None, Zip, Nada.
Luke 8:13 says they believed, but belief does not automatically save a person, only when and if God credits that belief as righteousness, does human faith provide access to God's grace of salvation.
Again, 1 Timothy 4:1 refers to turning from the truth of the gospel, and proclaiming false doctrines.
Again, Hebrews 3:12 clearly says the person has an unbelieving heart, thus never saved.
The fallacy underpinning your confusion seems to be acceptance that if you believe, that automatically saves, rather than the biblical truth, God has to credit your faith as righteousness in order to be saved.