I'm sorry to hear that you've been unable to send a payment. There's a list of things that you can check here. If all of those things have been resolved and the payments are still being declined, it is likely due to the security system. Sometimes a payment has one or more factors that make it a higher risk transaction. PayPal may decline a specific funding method or even the entire payment in those cases. You can try the payment with a different card or bank, or at a different time.
The security system is necessary to make the PayPal payment environment as safe as possible, and sometimes legitimate transactions are caught in the net. I'm sorry for the inconvenience.
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