Did the work of the Holy Spirit only happen during the New Testament time?

Pentecost is the event when the Holy Spirit came down and the disciples received the holy spirit and spoke in different languages.

Yesterday I was reading Psalms 51 and in verse 11 David prays to God that “Take not thy Holy Spirit from me”.

So was there Holy Spirit even before the Ascension of Jesus?

Even better, there was the triune God before the foundations of the earth. God the Father, God the Son and God the Holy Spirit are all eternal!

https://www.biblestudytools.com/topical-verses/bible-verses-about-the-trinity/

i do not think so. i think it also happen in the Old Testament too.

The holy spirit still works, and his work does not cease, but continues forever.