the Levites' portions had not been given to them

The full meaning of this statement can be made clear. This can also be translated in active form. AT: "the people had not been bringing into the storerooms their tithes and offerings of food for the temple priests" (See: rc://en/ta/man/translate/figs-explicit and rc://en/ta/man/translate/figs-activepassive)

they had run away, each to his own field, the Levites and the singers who did the work

"the Levites and the singers who did the work had left the temple, each one going to his own field"