"Getting one's hackles up" is a reference to animals that, in an effort to make themselves appear larger and more menacing, they will raise the hair on the back of their neck and down their back to serve as a visual warning to their apponent that the situation is reaching the flash point.
don't get angry or irritated
It means things are trustworthy.
To make a mistake
About to be sold, or given up.
say no to it
I would say they are being aggressive or scared.
It means shut up!
flatter her to get something
To keep struggling and not give up.
he suddenly turned up (to appear, emarge)
to make something stronger ,,
The hairs on the neck and back that stand up when a dog is showing aggression are called "hackles."