[MUMmer-help] Could not find any alignments while using "show-aligns"

[Rameez Mj <ram...@gm...>]

I am trying to align one draft genome contigs to another draft genome
contigs.I generated the delta file and proceeded for show-aligns command
like this

"show-aligns ref_qry.delta -r 30 33 > ref_qry.aligns" where 30 and 33 are
the names I wish to see in the alignment for both my draft sequences
respectively. But this commands shows "ERROR: Could not find any alignments
for 30 and 33". I am not able to resolve this,can anyone help me with
it.Thanks in advance.