Visually, it look good. Surface mount parts. The ones marked R1 and R2 are the pull down resistors. You can now test it with a single magnet. The two bigger black rectangles are the hall sensors. Test between ground and each signal wire. Without a magnet present, both signal wires should be zero volts. Bring the magnet to one, and you should see the signal switch to near 5v. It'll probably be pole sensitive, so flip the magnet if it doesn't work. Also it could be the opposite way round - held at 5v then pulled down to 0v when switched by the magnet.
If you get the same result as before, either a hall is faulty or one of the resistors. All the resistors do is conduct between ground and the signal wire. That's why I suggested manually adding one. They work by draining away the residual charge in the hall sensor after it's switched off. Without doing that, the signal wire stays high. When switched on, the charge coming in the 5v wire is massively more than what drains through the resistor, but the charge left behind when it switches off is tiny, so quickly dissipates through the resistor to ground.
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