Groupon complaint: Supply of Clematis

The offer on Groupon described the clematis as 7cm which is 70mm , so expectation was that the clematis would be at least slightly mature. For £9.99 it was expensive, so quality was expected. The photographs showed a flowering mature plant.
The clematis arrived in a box no bigger than 150mm and was a pot with a young seedling no bigger than 50mm tall. It was in poor condition and ly died after less than a week. I tried to get a refund on my account but none of the buttons in the refunds were live, so nothing happened. I tried to email without success and constantly got no response when trying to reach Customer Service.
I am also tired of trying to unsubscribe to Groupon having been inundated with twenty emails a day. Again none of the unsubscribe buttons actually work which must be illegal but short of changing my email address there is no way to prevent Groupon pestering me daily. This will be the last time I ever use Groupon for anything.