q2-shogun issues

I've been trying to run q2-shogun plugin. I run the following command:

qiime shogun nobunaga --i-query rep-seqs.qza --i-reference-reads refseqs.qza --i-reference-taxonomy taxa.qza --i-database bt2-database.qza --p-threads 25 --o-taxa-table taxatable.qza

But there was one error:

Plugin error from shogun:

Command '['shogun', 'assign_taxonomy', '-i', '/tmp/tmpe44h1m3w/alignment.bowtie2.sam', '-d', '/tmp/tmpe44h1m3w', '-o', '/tmp/tmpe44h1m3w/taxatable.tsv', '-a', 'bowtie2']' returned non-zero exit status 1.

Debug info has been saved to /tmp/qiime2-q2cli-err-xkdayr3i.log

Can anyone answer this question?
Thanks
Kelvin