--- title: FulfillmentConstraintRuleCreateUserErrorCode - GraphQL Admin description: >- Possible error codes that can be returned by `FulfillmentConstraintRuleCreateUserError`. api_version: 2024-10 api_name: admin type: enum api_type: graphql source_url: html: >- https://shopify.dev/docs/api/admin-graphql/2024-10/enums/FulfillmentConstraintRuleCreateUserErrorCode md: >- https://shopify.dev/docs/api/admin-graphql/2024-10/enums/FulfillmentConstraintRuleCreateUserErrorCode.txt --- # Fulfillment​Constraint​Rule​Create​User​Error​Code enum Possible error codes that can be returned by `FulfillmentConstraintRuleCreateUserError`. ## Valid values * CUSTOM\_​APP\_​FUNCTION\_​NOT\_​ELIGIBLE Shop must be on a Shopify Plus plan to activate functions from a custom app. * FUNCTION\_​ALREADY\_​REGISTERED A fulfillment constraint rule already exists for the provided function\_id. * FUNCTION\_​DOES\_​NOT\_​IMPLEMENT Function does not implement the required interface for this fulfillment constraint rule. * FUNCTION\_​NOT\_​FOUND No Shopify Function found for provided function\_id. * FUNCTION\_​PENDING\_​DELETION Function is pending deletion and cannot have new rules created against it. * INPUT\_​INVALID Failed to create fulfillment constraint rule due to invalid input. * MAXIMUM\_​FULFILLMENT\_​CONSTRAINT\_​RULES\_​REACHED Maximum number of fulfillment constraint rules reached. Limit is 10. *** ## Fields * [Fulfillment​Constraint​Rule​Create​User​Error.​code](https://shopify.dev/docs/api/admin-graphql/2024-10/objects/FulfillmentConstraintRuleCreateUserError#field-code) OBJECT An error that occurs during the execution of `FulfillmentConstraintRuleCreate`. *** ## Map ### Fields with this enum * <-|[Fulfillment​Constraint​Rule​Create​User​Error.code](https://shopify.dev/docs/api/admin-graphql/2024-10/objects/FulfillmentConstraintRuleCreateUserError#field-code)