Client is unable to finish paying the invoice

Description

I sent an invoice to my client but she said she’s having a problem finishing the transaction as it is not pushing through. According to her, the bank called her asking if she has a transaction with PayPal and confirmed that she is the one doing the transaction. Bank officer told her that they approved the transaction and said that the problem might be on my end. I just want to know if why my client, cannot pursue or finish settling the amount on the invoice I sent to my client? Note: This is my first time (Need urgent help)