The safety beam portion of the garage door opener is set up to stop the door from closing if something (car, person, etc,.) is in the doorway.
When the door is open - if you press the hard wired push button (not the wireless remote) the door will either close until shut completely, or begin to close and reverse direction as soon as you let go of the button. When this happens, it *usually* means that a sensor is blocked - and reversing the door motor. If you try yhtis with the remote the door may not move at all or just bump down and stop.
You should re-align the sensors as described in the link below. Good luck!
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