GFA file output size

[GeorgeBGM]

Hi, I want to align the assembled sequence (HJ.stLFR_CCS.maternal.fasta.gz HJ.stLFR_CCS.paternal.fasta.gz) to the human HPRC reference sequence (HPRC.Phase1.CHM13v2_Non-W.gfa) using the following command. The final GFA output (out.gfa) is smaller than the HPRC file, so how do we keep the entire HPRC reference sequence and add the assembled sequence to it as well.

 _minigraph  -cxggs  --ggen -l10k   HPRC.Phase1.CHM13v2_Non-W.gfa   HJ.stLFR_CCS.maternal.fasta.gz HJ.stLFR_CCS.paternal.fasta.gz  -t 30 > out.gfa_
 
 I'm looking forward to your reply