My first thought is that clematis require patience. If you planted a tiny plant, I might not expect it to bloom until the third year, and even then the bloom may be sparse. If you planted a larger plant, it may not be getting enough sun. Pretty much all clematis need at least 4 hours of sun, but some require more than that. I have a plant that is supposed to be Polish Spirit, but it grows in too much shade for it to have bloomed in the 5 or 6 years I've had it, even though other clematis growing on the same trellis bloom.

Can you give more information on the size of the plant when you planted it, the name of the clematis, and its growing conditions? You may get more specific suggestions if we have more information.