Hello, and thanks for your question! My name is XXXXX XXXXX I am happy to assist you today!!
From your description of the problem, it gives a pretty clear picture of whats wrong.
When this happens, its either 1 of 3 things and all are easy for you to repair
#1, the most common problem is that one of the electronic eye sensors has been bumped out of position and no longer sees the sensor on the other side of the door. They are located at the bottom of the door frame and are exactly across from each other. check the led lite and see if its flashing. If it is, then its out of position and you will need to move it back so it can see the other sensor.
#2, Bugs like spiders like to nest in the small inset where the laser is sitting. When this happens the sensors cant see each other and they think something is blocking the door. Clean the sensor and this may help.
#3, If #s 1&2 don't fix the problem then you have a mechanical issue. Check the small wires that connect the sensors and look for damage to the wire. If it all looks good then you may need to replace the snsors. They are available at any Lowes or Home Depot for around $20
The reason the door will close when hold the button down is because it is a built in safety. If the sensors think that there is a object under the door, it keeps the door from shutting to prevent harm to people or damage to the opener.
By holding the button down the opener knows that your not under the door and allows it to close.
I hope this helps answer your question. You seem to be offline, I need to step out for a while. If I was able to answer your question please be sure to leave positive feedback. If you still have questions, reply back to me on the post and I will reply back when I get back into the shop.
Thanks again, Charles
One of the sensors was out of place. I had cleaned the lenses but didn't notice that. Thank you.