Unable to access data in an Infotable

I am creating a service that needs to take in three Infotables and needs to access certain fields of data within them however when I try all I get is  

(Error in: RR.SA.SignatureViewMashupHelper.XaxisFixer javascript service. Message ::TypeError: Cannot read property "rows" from undefined (XaxisFixer#20))

the specific data i am accessing is a Infotable that is a data type in the larger infotable

this is very confusing as when i inspect the payload of the API call the key of the array that is that infotable is rows so why can i not access the data within.

here is the code snippet of the function

const reMapper = (obj) => {
 let returnObj = obj;
 return returnObj.Xaxis.rows.map((row) => row.value);
};

The infotable that "obj" refers to has the columns

SeriesId: String

SeriesTitle: String

XAxis: Infotable

YAxis: Infotable

SeriesLineColour: String

SeriesLineType: String

maxX: Number 

I have already tried turning the infotable into a JSON however that just leaves me with null instead