diff --git a/src/bootstrap.js b/src/bootstrap.js
index 1c482de..ab512e6 100644
--- a/src/bootstrap.js
+++ b/src/bootstrap.js
@@ -18,7 +18,7 @@ Joi.title = () => Joi.string().max(128)
 Joi.paymentStatus = () => Joi.string().valid('pending', 'partially-completed', 'completed', 'cancelled')
 Joi.xaiTemplate = () => Joi.string().valid(...allowedXAITemplates)
 Joi.interviewStatus = () => Joi.string().valid(...allowedInterviewStatuses)
-Joi.workPeriodPaymentStatus = () => Joi.string().valid('completed', 'cancelled')
+Joi.workPeriodPaymentStatus = () => Joi.string().valid('completed', 'scheduled', 'cancelled')
 // Empty string is not allowed by Joi by default and must be enabled with allow('').
 // See https://joi.dev/api/?v=17.3.0#string fro details why it's like this.
 // In many cases we would like to allow empty string to make it easier to create UI for editing data.
diff --git a/src/services/WorkPeriodPaymentProcessorService.js b/src/services/WorkPeriodPaymentProcessorService.js
index 7f30b6e..736cacb 100644
--- a/src/services/WorkPeriodPaymentProcessorService.js
+++ b/src/services/WorkPeriodPaymentProcessorService.js
@@ -65,7 +65,7 @@ processCreate.schema = {
     payload: Joi.object().keys({
       id: Joi.string().uuid().required(),
       workPeriodId: Joi.string().uuid().required(),
-      challengeId: Joi.string().uuid().required(),
+      challengeId: Joi.string().uuid().allow(null),
       amount: Joi.number().greater(0).allow(null),
       status: Joi.workPeriodPaymentStatus().required(),
       billingAccountId: Joi.number().allow(null),