Has anyone made a full one time payment on aidvantage?

Sorry to bother you guys. The way I have been paying off my student loans is by paying the min payment then once I have enough saved up just paying it off in full with fed loan. Now that they have switched me with aidvantage I cannot find any info on their website on how to make a full payment. I plan on contacting them sometime this week, but was hoping someone has experience with this so when I contact them I can be confident in what they're telling me to do.