Mapping incomplete, only one recharge, glitch or by design

I am trying to clean approximately 1,700 sf. The unit will start cleaning, use it’s complete charge properly, return to the recharge station, recharge and then start the second part of the cleaning process. When the unit finishes the second part of the cleaning process, it returns to the charger.

However, the unit has not finished cleaning the entire 1,700 sf area. As you can see in the attached photo, there is more space to clean. Unfortunately the unit does not complete the cleaning by starting the third cleaning session.

My question is; does the unit only recharge once to finish cleaning or does this unit have a problem?