Neither Snow nor Rain nor Zombies

I’ve done this side mission 2 times but even if I conclude it with success on the achievements not become lighted and I cannot finish the achievement of all side missions in kingsmought.

Could you help me?

I’ve just seen in my achievement’s log that that mission appear 3 times, 2 lighted, couse I’ve done it 2 times, and one not yet, so I cannot finish the achievement group, pls solve the bug.

There are three different missions. Two between the police station and the church, and another one at the sign between the bridge and the scrapyard.