Too Low of Light
Make sure that your coffee plant is getting enough light. These plants thrive in bright indirect light. In lower light spots, they likely won’t get enough energy to produce flowers. Try keeping it by an east window, or a few feet back from a south or west window.
Coffee plants come from tropical highlands. These plants like a lot of sun, but like a lot of rain as well. Coffee plants won’t flower if you don’t give them enough water, and they can be quite thirsty. Make sure that you water once 25% of the soil volume is dry.
Overwatering can be the culprit too. Many owners might overcompensate by watering their plants too often. Make sure you are testing the soil with your finger to be sure it is 25% dry before you give it a drink.
Coffee plants are picky about the temperature, preferring something between 65-80°F. Too chilly and the plant won’t thrive, and likely won’t flower at all. You should try to keep your coffee plants slightly warmer than room temperature. A lot of warmth and light, and they should be on track to flower.
A matter of time
One of the most common reasons a coffee plant isn’t blooming, isn’t really a problem at all. Coffee plants are simply very slow to flower. It can take anywhere from three to five years for a plant to reach maturity and start to flower. If you’ve only just received your coffee plant, it might just be a matter of time.