How can i fix the "Upload Error" that appears when i want to attach a file?

What type of file are you trying to upload? Please check that the file type, and file size meet the settings of your upload fields: 

https://www.jotform.com/help/29-How-to-Change-the-Allowed-File-Types-Extensions-in-the-Upload-Field 

https://www.jotform.com/help/33-Changing-the-File-Upload-Size-Limit 

If the issue continues, let us know if you allow us to try a real submission on your form, and share files you are trying to upload to do a more accurate test.

Hola,
Gracias por ponerte en contacto con CITRUS Comunicación Estratégica, en breve uno de nuestros ejecutivos le dará seguimiento a tu solicitud.
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Saludos cordiales,
CITRUS Comunicación Estratégica
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