Could be shortage of water, or lack of pollination - where's it growing, indoors, greenhouse? If its inside, and as its scotch bonnet, you may need to pollinate the flowers yourself...

Thanks. It is inside and it is watered regularly but not overly and I have been pollinating. I have cayenne and jalapeño growing as well which are doing fine outside. Puzzled?

No idea then, sorry

Mark, did you fertilize your chillis? If you used a high nitrogen fertilizer, that would cause 'blossom drop." Nitrogen is for growing leaves. They need phosphorous, potassium & trace elements to set fruit. They will eventually correct themselves in time depending on how much was used.