We have a 3300 Mitel and use 5320's for phones. I wanted to add a couple of 5302's in store rooms, but they don't seem to work. I added them, but when I go to pin them they don't work. I hit * - all lights flash - then #ext#***# According to what I read, the lights should all go out and dial tone in a minute or so. But with mine, the only thing that happens is the bottom two lights flash. Any idea what I am doing wrong? Thanks in advance.