There are some circumstances that the user can not subscribe to a product. Please check the following reasons:
① You don't have any balance of the currency of the product that you want to subscribe to
-> Please buy/deposit/convert the currency to have balance first.
② Remaining quota is 0
-> When the remaining quota of a product is 0, you can not subscribe to this product at that time. Please choose another product.
③ If there are any errors of the Earn screen, please contact us via email support@bitcastle.io to get further help.
If you have further inquiries, please don't hesitate to contact our Support Team via "Contact Us" function.