No Assig Taxonomy

Hi,
I met a problem,when i run the BLASTN program(import from BLAST),the results show that
Total reads: 181,372
Total weight: 66,179,721
With hits:181,372
Alignments:181,372
Assig Taxonomy:0
Numb. Tax. classes: 1
Class Taxonomy: 1

My file is .FA(nucleotide sequence),and my Taxonomy Accession mapping file is nucl_acc2tax-Nov2018.abin,I don’t know where the problem,so i want to consult you how to solve it.

Thanks.

which database are you aligning against?

NCBI-NR protein database.
today i used BLASTX program and the results unchanged
Total reads: 181,372
With hits: 181,372
Alignments: 181,372
Assig. Taxonomy: 0
MinSupport set to: 90
Min-supp. changes: 0
Numb. Tax. classes: 1
Class. Taxonomy: 1

my whole operation process as follow:
File→Import From BLAST→nucleotide sequence(.FA)→BLASTX→Taxonomy→Load Accession mapping file→prot_acc2tax-Nov2018X1.abin→Apply

Thanks

The problem is that didn’t provide the BLASTX file to MEGAN, but rather only the fasta file (twice).