Which Bird of Paradise is it, reginae or nicholai? The first one is the one with the orange blooms, the second one is the more tropical, Giant Bird and it gets white blooms but only does this after it gets Huge. In general, both can take full sun once acclimated, but reginae will put up with more drought and heat. In general, plants will fold their leaves in reaction to stress--could be excessive heat (if up against a brick building), drought, or root damage. What are your watering practices? Is the pot big enough? Too big? Post a pic if possible.

We keep ours in partial to full shade and we live in Florida. Keep in mind we are in Zone 10a in SW Florida and it gets very hot.