Are you absolutely sure you have a male and a female? Seems a silly question, but it seems unlikely they wouldn't be breeding otherwise. You can also check the environment and make sure the temps are correct, there's plenty of foliage for hiding, and a damp-ish soil area for egg laying.
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Torey
Eugene, Oregon, USA
1.1.3 Saharan Uros (Joe, Arthur, Hitch, Lefty, and Skywalker)
3.0 Mali Uros (Spike, Turtle, and Tank)
1.1 Ornate Uros (Scuttlebutt and Shazzbot)
1.3 Collared Lizards (Ripcord, Thiamine, Riboflavin, and Niacin)
2.0 Green Anoles (Bowser and Sprocket)
1.1 Chubby Housecats (Roscolux and Jenny)