Hi beads!
I understand that there are some who unnecessarily fear that they may or may not have committed this unpardonable sin, and since the Holy Spirit convicts all believers of sin, the person who fears that they might have committed this sin shows conviction, therefore cannot have committed this sin, if the Holy Ghost is blasphemed against then it would cease to convict the person of sin. Thats what I believe I'm not sure about others.
God Bless!