If you encounter an error message when attempting to send a payment, it could be due to the following reasons:

Email address confirmation: You may need to verify the email address associated with your PayPal account. Ensure that you have completed the necessary steps to confirm your email.

Funding source issues: There could be an issue with the funding source you have selected, such as insufficient balance or a declined transaction. Contact your bank or card issuer for further information and assistance.

Limitations on your PayPal account: It is possible that certain limitations have been placed on your PayPal account, which could restrict your ability to make payments. Check your account settings or reach out to PayPal customer support for clarification.

Limitations on the recipient's PayPal account: The recipient's PayPal account may have certain limitations that prevent them from receiving payments. You can inquire with the recipient or contact PayPal customer support for more information.

Security check requirements: PayPal may require you to go through a security check to confirm your identity before processing the payment. Follow the instructions provided by PayPal to complete the security check if prompted.

If you are experiencing difficulties with your bank account payment or encountering problems with your card, you can try the following:

Change your payment method at checkout: If you only have one payment method linked to your PayPal account, consider adding another payment method, such as a debit or credit card, or linking your bank account. This will provide you with additional flexibility during the checkout process.

Verify recipient information: Ensure that you have entered the recipient's email address or phone number correctly. It is important to confirm that the recipient has completed the registration process for their PayPal account, including confirming their information. Failure to complete this process can result in payment failures.

If you continue to experience issues, it is recommended to reach out to PayPal customer support for further assistance.

Please let me know if there is anything else I can help you with.