The Apostle John wrote the following three letters to the Churches but only letters one and three contain references to the Name of the LORD.
First Letter of John 2: 12 I am writing to you, children, because your sins have been forgiven for His Name’s sake.
First Letter of John 3: 23 And His commandment is this: we should believe in the Name of His Son, Jesus Christ, and love one another just as He commanded us.
First Letter of John 5:13 I write these things to you so that you may know that you have eternal life, you who believe in the Name of the Son of God.
Third Letter of John verses 5-8 Beloved, you are faithful in all you do for the brothers, especially for strangers; they have testified to your love before the church. Please help them in a way worthy of God to continue their journey. For they have set out for the sake of the Name and are accepting nothing from the pagans. Therefore, we ought to support such persons, so that we may be co-workers in the truth.
The Letter of Jude contains no references to the Name of the LORD