There is a theory that the main plot must revolve around your protagonist facing one problem and pursuing one goal.
While this may seem true on the surface level, it is not wholly true.
For example, in The Hobbit (2012), it seems like the goal is to reclaim the Dwarves' stolen mountain home from a dragon named Smaug (from the logline), or to seize the treasure held by Smaug. However, there are other underlying, and actually more important goals. For example, to change Bilbo.