WEX Bank Wawa Fleet Card Dishonest Late Fees Portland, ME Nationwide

After being a WEX Bank customer for several years through the WAWA Fleet Card program, I found a very disturbing fact about their late fees.  If you pay even a day late, the late fees are calculated not on the balance of the late payment, but rather for the balance of the late payment, any current charges that have not yet met their due date, and even unbilled transactions!  When asked about it, the first representative said they do this to offset losses by customers who create a balance and never pay them.  That is illegal.  The first supervisor said that it is their policy in their Terms and Conditions which can be updated at any time, not the Terms and Conditions I agreed to upon signing their agreement.  I was also told that these are not "Late Fees", but rather "Finance Charges" since they know what they are doing does not meet the legal definition of Late Fees, however they are listed as "Late Fees" on the invoice and she said she had no rebuttal for that.  Furthermore, when they send out updated Terms and Conditions, they do not send via e-mail or certified mail so there is no proof this was ever sent or received.  The first supervisor said she understood my frustration, but there is nothing they can do.  When I asked for the Terms and Conditions when we signed up, and was told that they don't have access to their own Terms and Conditions from 2013.  They have assured me that they will produce the Terms and Conditions along with the original application we signed, but it will take them time to find it.  Charging Late Fees on charges that are not late or not yet even billed is ILLEGAL!  There are probably countless more customers who have never taken the time to do the math and realize they have been ripped off by this Bank.