In RenewalSchema, the argument "attribute" is used to indicate Marshmallow where to parse the value from, but the correct argument is "load_from".

Author: JaviCerveraIngram

connect/models/schemas.py

@@ -203,7 +203,7 @@ def make_object(self, data):
 
 
 class RenewalSchema(BaseSchema):
-    from_ = fields.DateTime(attribute='from')
+    from_ = fields.DateTime(load_from='from')
     to = fields.DateTime()
     period_delta = fields.Int()
     period_uom = fields.Str()