Laptop not connecting to the closer AP

In work office, I have a 1800 sq ft space, with a dream router 7 as my main router at the front of the office. I also have one U7Pro connected via Cat6 off the PoE port of the dream 7 router. The U7Pro is in the middle back of the office, close to my personal office.

When I am in the back office, my laptop seems to always connect to the main Dream Router 7, not the much closer U7Pro.

How do I get my laptop to connect to the closer AP? I thought it should always just automatically connect.

I notice this when my wifi signal is not full in the top right of my macbook air, and speed tests show about 2/3 of the expected speed. When I'm connected to the U7Pro, I get basically full speeds.