The HS doesn't have a personal name--Why? Every being has a personal name.
Every important teaching where the Father and son are spoken of together--The HS gets 0 mention--Why?
Does the fact that the Holy Spirit not have a name mean He's not an actual person? By no means. Spiritual beings are not always named in scripture. More often than not, they are identified by their particular character-that is for demons they are called "unclean, "wicked", and so forth. Likewise the Holy Spirit is identified by His character which is "Holiness."
Also to note that the Watchtower uses the following Greek authorities in their literature- F.F. Bruce, A.T. Robertson, John N. Darby, Marvin R. Vincent, and W.E. Vine. And yet All of them believe that the Holy Spirit is a person.
And Jesus talked about the Holy Spirit on very important topics where He discussed the Father as well. The Holy Spirit is taught by Jesus with important teaching and promise. For instance, in three important chapters—John 14 through 16—the Lord Jesus opened His heart for the last time to His disciples. With compelling love, He poured out His soul. Shortly He would pour out His Spirit upon the disciples. In the record of His last hours with persons He had chosen to be with Him, and with words full of compassion, He spoke to them as friends. What He said was full of insight into what the Holy Spirit would mean in their lives after He went back to His Father.
These include testifying about Jesus in John 15:26:
"But when the Comforter is come, whom I will send unto you from the Father, even the Spirit of truth, which proceedeth from the Father, he shall testify of me."
Another time Jesus talked about the Holy Spirit is in a statement about His Resurrection for the forgiveness of sins and that it will be preached everywhere. You can't get any more important then that.
45 Then he opened their minds so they could understand the Scriptures.
46 He told them, "This is what is written: The Christ will suffer and rise from the dead on the third day,
47 and repentance and forgiveness of sins will be preached in his name to all nations, beginning at Jerusalem.
48 You are witnesses of these things.
49 I AM GOING TO SEND YOU WHAT MY FATHER HAS PROMISED; but stay in the city until you have been clothed with power from on high."
And as well as an important teaching if any, He talks about the Holy Spirit in being born again in John 3:6-8:
6 Flesh gives birth to flesh, but the Spirit gives birth to spirit.
7 You should not be surprised at my saying, 'You must be born again.'
8 The wind blows wherever it pleases. You hear its sound, but you cannot tell where it comes from or where it is going. So it is with everyone born of the Spirit."
So with the most important teachings Jesus ever taught (His death and resurrection, The forgiveness of sins, the Great Commission, being born again) He talked about the Hy Spirit in those same verses.