One of the frequent issues we come across is chimney odor. Here are some of the more common reasons why and the solutions.
The damper isn’t closed.
Make sure you have a cap and damper installed.
The chimney is not drafting properly, which could be multiple issues. At that point, I would suggest an inspection.
The wood you are using is unseasoned, which means it hasn’t dried long enough. Using properly seasoned wood and the right types of wood is important. One to avoid is eucalyptus.