T = int(input())
for z in range(T):
    N = int(input())
    lst = list(map(int, input().split()))
    idx = -999
    for i in range(N-2,-1,-1):
        if lst[i] < lst[i+1]:
            idx = i
            break
    if idx == -999:
        print(-1)
        continue
    j = idx + 1
    while j < N:
        if lst[j] <= lst[idx]:
            break
        j += 1
    lst[idx] , lst[j-1] = lst[j-1], lst[i]
    arr = lst[idx+1:]
    arr.sort()
    tmp = lst[:i+1] + arr[:]
    print(*tmp,sep = "")
 

VCA9IGludChpbnB1dCgpKQpmb3IgeiBpbiByYW5nZShUKToKICAgIE4gPSBpbnQoaW5wdXQoKSkKICAgIGxzdCA9IGxpc3QobWFwKGludCwgaW5wdXQoKS5zcGxpdCgpKSkKICAgIGlkeCA9IC05OTkKICAgIGZvciBpIGluIHJhbmdlKE4tMiwtMSwtMSk6CiAgICAgICAgaWYgbHN0W2ldIDwgbHN0W2krMV06CiAgICAgICAgICAgIGlkeCA9IGkKICAgICAgICAgICAgYnJlYWsKICAgIGlmIGlkeCA9PSAtOTk5OgogICAgICAgIHByaW50KC0xKQogICAgICAgIGNvbnRpbnVlCiAgICBqID0gaWR4ICsgMQogICAgd2hpbGUgaiA8IE46CiAgICAgICAgaWYgbHN0W2pdIDw9IGxzdFtpZHhdOgogICAgICAgICAgICBicmVhawogICAgICAgIGogKz0gMQogICAgbHN0W2lkeF0gLCBsc3Rbai0xXSA9IGxzdFtqLTFdLCBsc3RbaV0KICAgIGFyciA9IGxzdFtpZHgrMTpdCiAgICBhcnIuc29ydCgpCiAgICB0bXAgPSBsc3RbOmkrMV0gKyBhcnJbOl0KICAgIHByaW50KCp0bXAsc2VwID0gIiIpCiAgICA=