If you have downloaded it then you would need to speak to the author or Envato, but generally mistaken purchase and change of mind is out of scope for refunds.
Actually inside EU you have the right to retract from an online purchase within the first 14 days but that does not include digital goods after you have downloaded them.
Thanks you, yes I have downloaded and then I went back on Envato to see other templates, because I realized that the template I had chosen was too “empty”. I rushed it’s my fault. Thank you for your reply.