Please never send us your card details, we have no need for that information.
You can update your payment card details within your Shopify account which you can get to via Nature.com.
Once logged into your Nature.com account, go to the 'MyAccount' page and click on the Nature+ account overview link (example below).
[NOTE: sometimes this takes two attempts since there is a bug which we are working to resolve.]
From your Nature+ account, select Manage Subscriptions
Then go to the Payment Methods tab and click Edit payment Method
Click Send update email
The email you will receive should look like the below, and you can then use the link to update your payment details.
If you are having any difficulty and would like advice or support, please email Customer Service and use Nature+ in the header of your email, and give us many details or screenshots as you can and we will assist you.