Resolved. Request content was supposed to be:
{
"Name":"Boucher Fitness",
"Address":"276 North Drive",
"Address2":"",
"City":"Burlington",
"State":"MA",
"Country":"USA",
"Contact":"Gloria Boucher",
"Phone":"(617) 450-0083",
"SalesRep":"DKP",
"Comments":"",
"CreditLimit":667000...