#include<bits/stdc++.h>
using namespace std;
int main()
{
    int t;
    cin>>t;
    while (t--)
    {
        int n,k,i,cunt=0;
        cin>>n>>k;
        if (n%2==1)
        {
            if (n/2<k)
            {
                cout<<"-1"<<endl;
                continue;
            }
        }
        else
        {
            if ((n/2)-1<k)
            {
                cout<<"-1"<<endl;
                continue;
            }
        }
        int a[n];
        for (i=0;i<n;i++)
        {
            a[i]=i+1;
        }
        i=1;
        while (cunt!=k)
        {
            int temp;
            temp=a[i];
            a[i]=a[i+1];
            a[i+1]=temp;
            cunt++;
            i+=2;
        }
        for (i=0;i<n;i++)
        {
            cout<<a[i]<<" ";
        }
        cout<<endl;
    }
}
