How to import spreadsheets with words headers to notebooks in W. cloud ?

Hello. I am just starting to learn the use of notebooks.I have a problem when using Wolfram cloud after SetDirectory function, I can not import with SemanticImport function, spreadsheets that have words in headers ( names of variables), it appears an error that say: “the SemanticImport is not allowed while running in sandbox mode”. Also tried Import function. In desktop mathematica no problem.
Thank you ¡