Rietveld Refinement: Calculated Intensities far lower than observed for a small selection of miller indices

[![Calculated vs observed intensities for miller planes](https://i.stack.imgur.com/7qjOI.png)](https://i.stack.imgur.com/7qjOI.png)


I'm performing a Rietveld Refinement in excel of an I4/mcm material CeAlO3. The fit is very good for most peaks but on a few, I'm coming up very short on the intensities. Could this be due to a local instead of global minima and how would one remedy this situation?


