blasphemy is a sin you cant say anything bad about something that is holy

Yes, most blasphemy can be forgiven, but a biblical exception is the "blasphemy against the Holy Spirit," which is considered unforgivable. This unforgivable sin is sometimes interpreted as a persistent rejection of God's grace or salvation, rather than a single act of verbal blasphemy.
Forgivable and unforgivable blasphemy
Forgivable: According to the Bible, most sins and blasphemies can be forgiven, including speaking against the Son of Man. This is because the blood of Jesus is believed to be sufficient to cover all sins, as explained on Open the Bible.
Unforgivable: The exception is blasphemy against the Holy Spirit, which Jesus stated will not be forgiven "either in this world or in the world to come".
Interpretation: This unforgivable sin is often described as a willful and final rejection of God's offer of salvation through the Holy Spirit, leaving no room for repentance, note David Hernandez Ministries and Biola University. It is not about a single instance of blasphemous words but a persistent, hardened state of mind that rejects God's work.