Hi Amnon,
Thank you for the reply.
I have 24 samples, but 3 have fewer reads compared to the others, so I ran analyses with and without them. I ran a pick_open_reference_otus.py with default settings, and then core_diversity_analyses.py with default settings, setting the minimum number of reads to 50,000 to exclude the ones with fewer reads. I also tried to run beta_diversity_through_plots.py and had the same issue.
I can share the data with you if you would be willing to have a look. Please let me know.
Thanks again!
Best wishes,
Francine