diff --git a/web/app/assets/javascripts/react-components/BookLessonFree.js.jsx.coffee b/web/app/assets/javascripts/react-components/BookLessonFree.js.jsx.coffee
index 7c8a12fb7..a40997576 100644
--- a/web/app/assets/javascripts/react-components/BookLessonFree.js.jsx.coffee
+++ b/web/app/assets/javascripts/react-components/BookLessonFree.js.jsx.coffee
@@ -132,21 +132,31 @@ proficiencyDescriptionMap = {
     else
       context.location = '/client#/jamclass/payment'
 
+  resetErrors: () ->
+    @setState({generalErrors:null, slot1Errors:null, slot2Errors:null, descriptionError:null})
   failedBooking: (jqXHR) ->
     if jqXHR.status == 422
       body = JSON.parse(jqXHR.responseText)
 
-      logger.debug("BODY", body)
       generalErrors = []
       for errorType, errors of body.errors
         if errorType == 'description'
           @setState({descriptionError: errors})
-        else if errorType == 'lesson_booking_slots'
-          @setState({})
         else
           error = {}
           error[errorType] = errors
           generalErrors.push(errors)
+
+      for childErrorType, childErrors of body._children
+        if childErrorType == 'lesson_booking_slots'
+          slot1Errors = childErrors[0]
+          slot2Errors = childErrors[1]
+          if Object.keys(slot1Errors["errors"]).length > 0
+            @setState({slot1Errors: slot1Errors["errors"]})
+          if Object.keys(slot2Errors["errors"]).length > 0
+            @setState({slot2Errors: slot2Errors["errors"]})
+        if childErrors.length > 0
+          @setState({childErrorType, childErrors})
       @setState({generalErrors: generalErrors})
 
   onCancel: (e) ->
diff --git a/web/app/controllers/api_controller.rb b/web/app/controllers/api_controller.rb
index 421350c61..e202c509e 100644
--- a/web/app/controllers/api_controller.rb
+++ b/web/app/controllers/api_controller.rb
@@ -40,14 +40,14 @@ class ApiController < ApplicationController
   protected
 
     def recursive_errors(model, children)
-      response = {errors:model.errors.to_json, _children:{}}
+      response = {errors:model.errors, _children:{}}
       children_response = response[:_children]
       children.each do |child|
         child_response = []
         associations = model.send(child)
         if associations
           associations.each do |association|
-            child_response << {errors: association.errors.to_json}
+            child_response << {errors: association.errors}
           end
         end
         children_response[child] = child_response