PrestaShop checkout page - optimize the connections to PayPal

I am looking for an expert to create a simple checkout page on my PrestaShop website and optimize the connections to PayPal at this time customers getting error or can not pay. we receive Paypal message- check your server that handles PayPal Instant Payment Notifications (IPN). IPNs sent to the following URL(s) are failing. I would like to have two payment options on the checkout page 1. Payment with credit card via PayPal 2. Payment with Paypal account The default method should be the credit card and clients could choose PayPal as a second method. (See image provided) Default currency is Euro . Default language if French . Site is mostly service French clients Payment page terms must be in FRENCH language. See example of how the checkout should look You are responsible for testing the checkout on YOUR sanbdbox Paypal account and making sure it works with IE Explorer, FireFox, Chrome BEFORE you move it to production You must be an expert in PayPal checkout processes and APIs. I need this work done in 3 days. Payment must be working 5 days without errors before full payment.