USCIS fee payment website error

My wife was approved to enter the United States and we have bought flights.

I have attempted to pay the immigrant fee on the USCIS website but I have been getting an error for 5 straight days.

Will this cause a problem for her to enter into the United States if the fee is not paid?

I have called the phone number and emailed in order to try to resolve the problem. I have not been able to speak to anyone over the phone and no response to my email requesting assistance at this time.