There are a few possible reasons for declined transaction when you pay via card or mobile provider:

- insufficient funds on the account
- automatically added purchase limits for online payments from your bank or operator for various reasons (it is possible to have automatic added limits for the number of transactions per hour or per day)
- inability to pay from company phone numbers

In such cases, it is best to contact the support team of the bank or operator to get more information about the reason for the rejection of the transaction.