Show me in the Bible where it says believers become "UN-sealed" by the Holy Spirit. Believers are described as faithful and are sealed
UNTO/FOR the day of redemption (Ephesians 4:30).
Vine's Expository Dictionary of NT Words
<1,,728,arrabon> originally, "earnest-money" deposited by the purchaser and forfeited if the purchase was not completed, was probably a Phoenician word, introduced into Greece. In general usage it came to denote "a pledge" or "earnest" of any sort;
in the NT it is used only of that which is assured by God to believers; it is said of the Holy Spirit as the Divine "pledge" of all their future blessedness, 2 Corinthians 1:22; 5:5; in Ephesians 1:14; 4:30 particularly of their eternal inheritance.
2 Corinthians 1:21 - Now it is God who makes both us and you stand firm in Christ. He anointed us, 22
set his seal of ownership on us, and put his Spirit in our hearts as a
deposit, guaranteeing what is to come.
2 Corinthians 5:5 - Now it is God who has made us for this very purpose and has given us the Spirit as a
deposit, guaranteeing what is to come.
Ephesians 1:13 - In Him you also trusted, after you heard the word of truth, the gospel of your salvation; in whom also, having believed, you were
sealed with the Holy Spirit of promise, 14 who is the
guarantee of our inheritance until the redemption of the purchased possession, to the praise of His glory. Praise God!