Hello,
Probably you have uploaded your template not to root directory but to subdirectory named for example '/test'. So you should add /admin after /test so it would be http://www.your_website_domain / test / admin.
If it is not your case please create new request providing your FTP access details so our agents could look into this issue for you. Note: do not provide your FTP details here but create new request so no one could see your FTP details.
Best regards,
Mathew Brown