A picture always helps. It is possible you are doing everything right but the plant prefers something else. Move it a few feet or give it more or less than before. I had one that finally bloomed 10 years later and it was pitiful. Google the plant name with the word culture after the name. That should give you the various requirements.

When in doubt, increase light. Usually works.

Jane

I grow my Bllra just like my onc. and have had no problem with it blooming. In fact it is blooming now for the second time this year which I didn't expect.