Help me in solving SESO43 problem

help
,
1

My issue

stack overflow error

My code

public static void mergeSort(int[] arr, int left, int right) {
    // Write your code here
     if(left>=right)
    {
        return;
    }
    int mid=left+(right-left)/2;
    mergeSort(arr,left,mid);
    mergeSort(arr,mid,right);
    merge(arr,left,mid,right);
    
}
public static void merge(int arr[],int left,int mid,int right)
{
    int temp[]=new int[right-left+1];
    int i=left;
    int j=mid+1;
    int k=0;
    
    while(i<=left&&j<=right)
    {
        if(arr[i]<arr[j])
        {
       temp[k]=arr[i];
        i++;
        } 
    else{
        temp[k]=arr[j];
        j++;
    }
    k++;
}
while(i<=left)
{
    temp[k++]=arr[i++];
}
while(j<=right)
{
    temp[k++]=arr[j++];
}
//copy temp array to original array
for(k=0,i=left;k<temp.length;k++,i++)
{
    arr[i]=temp[k];
}
}

Learning course: Design and analysis of Algorithms
Problem Link: https://www.codechef.com/learn/course/abesit-daa/ABESITDA21/problems/SESO43