how to get the supplementary alignment

I used graphmap with the command as  follows:
```shell
$GRAPHMAP align \ 
    -r $REF \ 
    -i $IDX \ 
    -d $FQ \ 
    -t 20 \ 
    --ambiguity 0.02 \ 
    --secondary \ 
  -o $OU
```
But, the result cannot get the secondary and supplementary alignment.