func (resource *EnrollmentResponse) MarshalJSON() ([]byte, error) {
	resource.ResourceType = "EnrollmentResponse"
	return json.Marshal(*resource)
}
Custom marshaller to add the resourceType property, as required by the specification
package models
import (
	"encoding/json"
	"errors"
	"fmt"
)
type EnrollmentResponse struct {
	DomainResource                `bson:",inline"`
	Identifier                    []Identifier  `bson:"identifier,omitempty" json:"identifier,omitempty"`
	Status                        string        `bson:"status,omitempty" json:"status,omitempty"`
	RequestIdentifier             *Identifier   `bson:"requestIdentifier,omitempty" json:"requestIdentifier,omitempty"`
	RequestReference              *Reference    `bson:"requestReference,omitempty" json:"requestReference,omitempty"`
	Outcome                       string        `bson:"outcome,omitempty" json:"outcome,omitempty"`
	Disposition                   string        `bson:"disposition,omitempty" json:"disposition,omitempty"`
	Ruleset                       *Coding       `bson:"ruleset,omitempty" json:"ruleset,omitempty"`
	OriginalRuleset               *Coding       `bson:"originalRuleset,omitempty" json:"originalRuleset,omitempty"`
	Created                       *FHIRDateTime `bson:"created,omitempty" json:"created,omitempty"`
	OrganizationIdentifier        *Identifier   `bson:"organizationIdentifier,omitempty" json:"organizationIdentifier,omitempty"`
	OrganizationReference         *Reference    `bson:"organizationReference,omitempty" json:"organizationReference,omitempty"`
	RequestProviderIdentifier     *Identifier   `bson:"requestProviderIdentifier,omitempty" json:"requestProviderIdentifier,omitempty"`
	RequestProviderReference      *Reference    `bson:"requestProviderReference,omitempty" json:"requestProviderReference,omitempty"`
	RequestOrganizationIdentifier *Identifier   `bson:"requestOrganizationIdentifier,omitempty" json:"requestOrganizationIdentifier,omitempty"`
	RequestOrganizationReference  *Reference    `bson:"requestOrganizationReference,omitempty" json:"requestOrganizationReference,omitempty"`
}