Initiate_transfer_error when uploading theme on wordpress.com business plan

Hello,

I just purchased Unicon to add to our new business account on WordPress.com. I have downloaded the ‘Installable WordPress File Only’ and attempted to upload the zip file to WordPress but am receiving an ‘Initiate_transfer_error’ each time I try. I have not yet mapped my custom domain to WordPress as it is currently pointing to our Squarespace website and I would like to create this new WordPress site before mapping it. In order to conduct an FTP upload, it appears I would need to connect to my hosting so I am a bit confused as to where to go from here. Can you please confirm why I am receiving this error with uploading the ‘Installable WordPress File Only’ zip folder in WordPress and how I can resolve it?

Best,
George

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