trying to replace a light switch with motion sensitive switch

Hi, i'm VERY new homeowner and I'm trying to do little projects on my own.
I bought THIS switch. I was trying to put it in a hallway where a light is controlled by 2 switches, one at each end of hallway.
The switch that I tried to replace had 4 wires. I removed them from the old switch and attached it to the motion-sensitive switch, black to black, red to red, white to white and green to ground wire. When I tested the switch did not work (light did not turn on). What could I have done wrong?

Then, I took the wires off and put it back on the old switch. I admit, I did not remember which terminal each wire went to except for the ground wire, so I guessed and attached the wires. Now switch works but light turns on only when switches on each end of hallway are in on position. If either of them is in off position, light does not turn on. Is it possible to know which wires would I need to to switch to fix this?

Thank you in advance.

 

You are going to need to determine if the motion sensor needs a neutral. If all 3 wires were connected to the 3 way switch the white is not a neutral.

Do both boxes have just a black, a white and a red? Ignore any green or bare.

 

That motion sensor does require a neutral.
The easiest way to handle this is to post a picture or two of your wiring..... How-to-insert-pictures.

 

so, I did figure out that there is a neutral wire. The wires in my electrical boxes are not color-coded appropriately! I was able to successfully connect the motion sensor switch and it powered up but I was unable to turn the light on. It turns out that this switch is not for a 3-way connection. I am guessing it will not be possible to use a single-pole switch on a 3-way circuit?

(I have attached a picture of connections on the current switch. White is the live wire)

 

White is the feed to the switch as required by code. It is not a neutral. You need a motion sensor that does not require a neutral.