Struggle to pay payflex

I used payflex before and again in December. In January although I have funds in my account I got a message saying payment failed with an amount that included a penalty.

I changed jobs in January and my email address changed. . I contacted payflex to ask what the reason was for the failed payment and to pay the account. Since the 9th January there has been numerous email to and from payflex. I have asked several times to be debited for the full amount or to get a link to pay the full amount but they can't help me because of the email address.

Although I opened the account without sending my ID I now can't pay the account because I have a book I'd and not a smart ID.

In the meantime payflex will continue to add on extra charges. The end of the email conversation says that they cannot help me further.

At this time I have no leave or desire to follow the loooong process of getting a smart ID and now payflex is unable/unwilling to help me change the email address in my account so I can pay my account.

I feel so frustrated and helpless. Who do they think the person is, who is trying to hack someones account so they can pay it? Even a link to pay my bill or banking details for an eft will be helpful!