Another biblical reason why we understand that it is not appropriate to pray to the holy spirit is that the ancient servants of God asked God Himself to allow them to continue enjoying that spirit of Him in their lives. Here, for example:
Psal. 51:11 Do not throw me away from before your face;
And your holy spirit O do not take away from me.
... David is begging Jehovah not to take away His spirit because of the sin he had committed in connection with Bathsheba. Notice that David did not refer to the holy spirit as a God-person, but as Jehovah's spirit, and that it was under Jehovah's total control; something that Jehovah could give or take from his servants.
Here:
Is. 63:10 But they themselves rebelled and made his holy spirit feel hurt. He now was changed into an enemy of theirs; he himself warred against them. 11 And one began to remember the days of long ago, Moses his servant: “Where is the One that brought them up out of the sea with the shepherds of his flock? Where is the One that put within him His own holy spirit?
... once again, the holy spirit is not mentioned as an independent person, but as something under Jehovah's control that he uses to relate to his human servants ... so it is not considered either here as a person, but as a spiritual energy that comes directly from Jehovah and is deposited in his faithful servants, and that He can give or take from them depending on how the person disposes of that spirit or acts accordingly with the purpose for the one who was anointed with him.
In verse 10 it says that His people were resisting the influence of Jehovah's holy spirit (compare with Eph. 4:30), and in verse 11 it is stated that this spirit was acting primarily through Moses, who had been the depositary of that spirit from Jehovah.
Taking into account what these passages teach us about the servants of Jehovah of old, we understand that the one who must be prayed to give us his holy spirit is God himself, and not his spirit as if it were some person with separate identity.
Luke 11:13 Therefore, if you, although being wicked, know how to give good gifts to your children, how much more so will the Father in heaven give holy spirit to those asking him!”