Envato theme error

Envato Customers Web and Code
1

I am trying to load gullu agency template on my site and getting the following error. I am very new to wordpress and envato, any help will be appropriated.

{
	"error": {
		"context": "uploadTemplateKitZipFile",
		"code": "zip_failure",
		"message": "Please upload a valid Template Kit zip file",
		"data": [ ]
	}
}