Certified GKH Gardening Expert
This will be due to a lack of dormancy. This is necessary to get it to bloom. Taper off watering a little at a time until the leaves start to die off. Once this is done, it will need a rest period in a dark, cool location for anywhere between 1 and 3 months. After, you will introduce it to light, slowly while starting to water as well.
By this time, it should be blooming.