Thanks for writing. Be sure your mock orange is growing in full sun; if it gets too much shade, it won't bloom well --- if at all.
Also: Do you prune it at all? The time to cut back mockorange is mid-June, right after the plant finishes blooming. If you cut it back in fall, winter, or early spring, you could be cutting off the flowers.
Is it a mock orange variety that's adapted to your climate? If you have one that's not quite hardy for you, the flower buds could be freezing out every winter.
---Justin, Senior Garden Editor, BHG.com