Hi @Karthika,
Thanks for reaching out! :qiime2:
This error is typically related to the UTF-8 encoding (either what's set in your machine locally, or in your input file). Check out this forum post for a few possible solutions (setting your machine's default to UTF-8, re-saving your file in UTF-8 format, double checking your file contents), and let us know if you're still running into the same error after giving those things a try!
Cheers 