the holy spirit is the second witness
all wich is ment by Matthew 12:31-32 is "blaspheme against the son of man is forgivable, blaspheme against the second witness is unforgivable" Bear in mind that in the Bible, a prosecution requires no less than two witness (Deut 19.15; Matt 18.16; John 8.17; 2 Cor 13.1; 1 Tim 5.19; Heb 10.28).
Jesus’ warning against blasphemy against the Holy Spirit means we should of repented the first time.
“A man who hardens his neck after much reproof will suddenly be broken and there is no remedy” -- Proverbs 29:1