It relates that the ring of Bilgah in the Temple is stuck and closed forever because she apostasized and intermarried with a soldier from the kings of Greece. When the Gentile soldiers came and entered the Temple, Miriam struck the top of the altar.
This passage recounts that the ring of Bilgah within the Temple has been permanently locked because she abandoned her faith and married a Greek soldier.  When Gentile soldiers arrived at the Temple, Miriam struck the altar's peak.