No species selected from prescreen in HUMAnN3

Hi everyone,
I’m using HUMAnN3 to analyze shotgun metagenomics sequences from hair microbiome samples. These samples were subset to the lowest read depth out of the pool of samples using seqtk, then concatenated. I received this output on my first sample, and I am concerned about why this has occurred:

Running metaphlan …

Total species selected from prescreen: 0

Selected species explain 0.00% of predicted community composition

No species were selected from the prescreen.
Because of this the custom ChocoPhlAn database is empty.
This will result in zero species-specific gene families and pathways.

I am concerned and wondering what could have caused this issue. Could this be caused by extreme host DNA contamination, or do I just need to make the settings in HUMAnN3 less sensitive? I’ve also attached my log so far (diamond is still running for the alignment to reference database).
log_2_24_2020_troubleshoot.txt (6.3 KB)

Are you running multiple samples and getting this error for all of them?
I have been getting this error in some of my samples, and I am unable to pinpoint where I am going wrong.