Error in uploading data

I have been facing trouble uploading marker gene data inputs. The format has been changed according to the given instructions, but still no luck!
I have exported QIIME2 artifacts and adjusted the format based on the instructions, both .txt format as well as in .csv format. I used Silva based classifier for Taxonomic assignment, so in the taxonomy label I should ideally choose SILVA Taxonomy , is that right?

Also I have around 137 samples in abundance.txt and taxonomy.txt so, I was wondering if there is a limit to file size?

Can I get some guidance?
Thanks in advance.