Radix sort Issues??? Help

I am having issues getting this Radix sort program to work properly. I know I am overlooking something but I am at a loss to what it is.

Code Java:

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public class SortArrayAll{
 
	public static void radixSort(String[] array, int n, int d){
	    ADTQueue<String>[] sort = new ADTQueue[n];
        for (int k = 0; k < n; k++){ // create ADTQueue based on size of array
            sort[k] = new ADTQueue();
        }
        for(int i=0; i<d;i++){
            for(int j=0; j<n;j++){
               char num = (array[j].charAt(i));
               int sort1 = Integer.parseInt(Character.toString(num));
                 sort[sort1].enqueue(array[j]);
            }
           int Counter=0;
              for(int k=0; k<sort.length;k++){
 
               while(!sort[k].isEmpty()){
                 array[Counter]=(String)sort[k].dequeue();
                 Counter++;
               }
 
               //you need to implement this sorting method
             }
          }
       }
 
 
	public static void main(String[] args){
		String[] array = GenerateData.getData(20);
		int n = array.length;
		int d = array[0].length();
 
		System.out.println("Origianl Data");
		displayArray(array);
 
		radixSort(array, n, d);
 
		System.out.println("\nSorted Data");
		displayArray(array);
 
	}
 
	static <T> void displayArray(T[] array){
		for(int i=0;i<array.length; i++){
			System.out.print(array[i]+" ");
		}
			System.out.print("\n");
	}
 
}

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Can you explain in more detail what the problem is?

The sort method will only sort single digit variables it will not sort double digit variable correctly.