[TITLE] help me find this manwha

Hi, how are you? I'm here to ask for help finding a manhwa. I don't have any pictures or anything, but I vaguely remember the beginning and a bit of the plot.

The story begins with FL in a cafe, breaking off her engagement and demanding the return of the rights to a mine/territory in a forest.

I don't know if this will help, but FL's sister is a sort of knight, and one day she finds FL's ex-fiancé's carriage and threatens him to return the rights.

Later in the plot, FL hires mercenaries and knights from the family to venture into the area to develop it. I don't know if this will be helpful, but it's what I remember most about the manhwa, and I haven't been able to find it to reread it.