How do I pay for DPR?

Could you please clarify the process for paying for DPR? Is there a specific platform or method that you recommend using to make payments? Also, are there any fees associated with the payment process that I should be aware of? Additionally, how long does it typically take for the payment to be processed and reflected in my DPR balance? Lastly, are there any security measures in place to ensure the safety of my payment information?