If it’s the middle of summer and your plant is strictly green, check for these "bloom killers":
If your plant is looking a bit green and dull, try these tips from experts like The Spruce and Monrovia : do bougainvillea bloom year round
Trim back the ends of the branches by a few inches. This forces the plant to branch out, creating more "new wood" where future bracts can form. If it’s the middle of summer and your
Do bougainvillea bloom year-round?