Ezra 2:61-63

And from among the priests: the descendants of Hobaiah, the descendants of Hakkoz, and the descendants of Barzillai (who had married a daughter of Barzillai the Gileadite and was called by their name).

These men searched for their family records, but they could not find them and so were excluded from the priesthood as unclean.

The governor ordered them not to eat the most holy things until there was a priest to consult the Urim and Thummim.