Then shall they cry unto the LORD, but he will not hear them: he will even hide his face from them at that time, as they have behaved themselves ill in their doings.
Then - at the time of judgment, which Micah takes for granted, so certain is it (cf. Micah 2:3, "Behold, against this family do I devise an evil, from which ye shall not remove your necks").
Shall they cry unto the Lord, but he will not hear - just as those oppressed by them had formerly cried, and they would not hear. Their prayer shall be rejected, because it is the mere cry of nature for deliverance from pain, not that of repentance for deliverance from sin.
He will even hide his face from them at that time, as they have behaved themselves ill in their doings - men cannot expect to do ill and fare well.