Some hymns to the Holy Trinity (triadika, troitseny) from the coming series of readings of the Great Canon of St Andrew of Crete:
O Trinity above all essence and worshipped as One God, take from me the heavy burden of sin, and in Your compassion, grant me tears of repentance.
O God of all, I sing of You as One yet Three in Person, Father, Son and Holy Spirit.
O God, Trinity yet One, save us from delusion, temptations and misfortune.
I confess You as one God in Trinity, a single essence unconfused in persons, co-enthroned and co-ruling, and I sing to You the great song thrice sung on high.
I am the Trinity, simple and undivided in essence yet divided in Persons. I am also the Unity united in nature, says God, the Father, the Son, and the divine Spirit.
Simple and undivided, One in essence and nature, Light and Lights, One Holy and three Holies, God is praised as Trinity. So sing praises to Him, O my soul, and glorify the Life and Lives, the God of all.
We glorify the Father, we exalt the Son, and we worship the Holy Spirit, the indivisible Trinity who exists as One, the Light and Lights, the Life and Lives who grants light and life to the ends of the world.
If you were to search through other canons for more such hymns, you would find many similar examples expressing the complete equality of the Spirit with the other persons of the Holy Trinity. There is no question at all that the Holy Spirit is nothing less than God. To say that we can't use the term "God the Holy Spirit" would mean the term "God the Son" is also wrong, which is clearly not the case.