Okay, here comes the next logline request. Just to recap - a logline is a one-sentence summary of your story that consists of three major elements: the character, the character's goal and whatever stops them from reaching that goal (circumstances, antagonist etc). Ideally, a logline should list the stakes of your novel, the key conflict.

Here is the original logline

When a feisty princess and a flirty prince belonging to two rival kingdoms are forced to work together, things start to get complicated. Will they be able to push aside their differences and also the growing attraction between them for the benefit of their kingdoms?

Feedback: 

At first sight, this doesn't sound too bad, but I see two issues a) It's more of a blurb than a logline b) Not only does it sound rather vague, it also gives the impression of the story being very "trope". I'm sure it isn't, but the blurb doesn't do it justice. 

Focus should be on bringing out the originality. That can be done by being more specific. How do they work together? What exactly  is the problem and what do they want to do about it? I would definitely NOT add the open question in the second sentence. Not even for blurbs is that considered to be a good approach. 

Here are two examples of loglines, hopefully that will demonstrate what loglines are. 

THE MATRIX

A computer hacker learns from mysterious rebels about the true nature of his reality and his role in the war against its controllers.

MY NOVEL GONE WITH THE TIDE

To save the love of her life, Mel will have to kill him. 

Reworked version of logline

Well, I can't give you one, since I don't know enough about the novel. However, it could run something along these lines 

A feisty princess and a flirty prince (I like that!) have to overcome their family's feud to (save the king from the dragon, stop the royal banquets from getting poisoned - whatever. Be specific) - and manage not to fall in love. 

Something along those lines should work and it will bring out your conflict into the open.