Change payment dates, assist me to make arrangements

I send a query at payflex to ask them to change payment dates for me because when on the system it shows that I have selected the option to make payments every after 2 weeks which is not going to be possible for me because I get paid on the first of each but they keep on saying that they cannot assist me on that matter. All I want is for them to change payment date before my next payment, today I called them around 10:00 to query about this but the lady kept on saying that is not possible ,I am very disappointed because thier customer service is unable to assist customers whereas when you have errors they are able to make new arrangements worst part I ask the lady his fullness but she only said her name is Benedict and she said unfortunately she cannot disclose her surname, how come we as their clients we trust them with our personal information , before they can assist you, the ask you to verify your ID no,contact details, emails but the lady refuse just to give me her surname. Bad customer service ever!