in reply to Issues with XLSX.pm,
I presume you are referring to Spreadsheet::XLSX? Is it properly installed? There should be additional pm files under the XLSX dir with the pm file.
However, the error suggests you are not using a Spreadsheet::XLSX object when calling the add_worksheet method.
There are very limited details in your post so it is hard to provide anything but guesswork. Could you please provide an SSCCE?
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