Months displaying in two different ways, need to standardize

Hi there,

I recently inherited a large data analysis project in which we have numerous pivot charts feeding off the same dataset. Two of these charts are plotting various metrics by months that span 2012-2013. I currently have the two pivotcharts both set up with Year and Month on the horizontal axis field. However, on one chart the months are displayed by name (i.e. Jan, Feb, Mar), but on the other they display numerically (1,2,3). The raw data uses numerical values for the months, but somehow one of the two charts was able to covert to name format (it was there before I took over the project). Is there a way to standardize this? I would share the file with you all but am unable due to company NDA policy.

Thanks for any help!

Elliott