diff --git a/models/workflow/workflow_mongo_accessor.go b/models/workflow/workflow_mongo_accessor.go
index 719783b..3faa246 100644
--- a/models/workflow/workflow_mongo_accessor.go
+++ b/models/workflow/workflow_mongo_accessor.go
@@ -2,6 +2,7 @@ package oclib
 
 import (
 	"errors"
+	"strings"
 	"time"
 
 	"cloud.o-forge.io/core/oc-lib/dbs"
@@ -10,7 +11,7 @@ import (
 	"cloud.o-forge.io/core/oc-lib/models/utils"
 	"cloud.o-forge.io/core/oc-lib/models/workflow_execution"
 	"cloud.o-forge.io/core/oc-lib/models/workspace"
-	"github.com/vk496/cron"
+	cron "github.com/robfig/cron/v3"
 	"go.mongodb.org/mongo-driver/bson/primitive"
 )
 
@@ -40,7 +41,7 @@ func (wfa *workflowMongoAccessor) CheckBooking(start *time.Time) bool {
 func (wfa *workflowMongoAccessor) getExecutions(id string, data *Workflow) ([]*workflow_execution.WorkflowExecution, error) {
 	workflows_execution := []*workflow_execution.WorkflowExecution{}
 	if data.Schedule != nil {
-		if data.Schedule.Start == nil || data.Schedule.Start.IsZero() {
+		if data.Schedule.Start == nil {
 			return workflows_execution, errors.New("should get a start date on the scheduler.")
 		}
 		if data.Schedule.End != nil && data.Schedule.End.IsZero() {
@@ -50,11 +51,18 @@ func (wfa *workflowMongoAccessor) getExecutions(id string, data *Workflow) ([]*w
 			if data.Schedule.End == nil {
 				return workflows_execution, errors.New("a cron task should got a end date.")
 			}
-			c, err := cron.Parse(data.Schedule.Cron)
+			cronStr := strings.Split(" ", data.Schedule.Cron)
+			if len(cronStr) < 6 {
+				return nil, errors.New("Bad cron message: " + data.Schedule.Cron + ". Should be at least ss mm hh dd MM dw")
+			}
+			subCron := strings.Join(cronStr[:6], " ")
+			// cron should be parsed as ss mm hh dd MM dw t (min 6 fields)
+			specParser := cron.NewParser(cron.Second | cron.Minute | cron.Hour | cron.Dom | cron.Month | cron.Dow)
+			sched, err := specParser.Parse(subCron)
 			if err != nil {
 				return workflows_execution, errors.New("Bad cron message: " + err.Error())
 			}
-			for s := c.Next(*data.Schedule.Start); !s.IsZero() && s.Before(*data.Schedule.End); s = c.Next(s) {
+			for s := sched.Next(*data.Schedule.Start); !s.IsZero() && s.Before(*data.Schedule.End); s = sched.Next(s) {
 				obj := &workflow_execution.WorkflowExecution{
 					AbstractObject: utils.AbstractObject{
 						Name: data.Schedule.Name,
diff --git a/models/workflow/workflow_schedule.go b/models/workflow/workflow_schedule.go
index 657d369..18d0712 100644
--- a/models/workflow/workflow_schedule.go
+++ b/models/workflow/workflow_schedule.go
@@ -7,7 +7,7 @@ type WorkflowSchedule struct {
 	Name  string     `json:"name" bson:"name" validate:"required"`
 	Start *time.Time `json:"start" bson:"start" validate:"required"`
 	End   *time.Time `json:"end,omitempty" bson:"end,omitempty"`
-	Cron  string     `json:"cron,omitempty" bson:"cron,omitempty"`
+	Cron  string     `json:"cron,omitempty" bson:"cron,omitempty"` // ss mm hh dd MM dw task
 }
 
 func (ws *WorkflowSchedule) GetAllDates() (timetable []time.Time) {