diff --git a/internal/booking/models.go b/internal/booking/models.go
index 3d03a06..bce7855 100644
--- a/internal/booking/models.go
+++ b/internal/booking/models.go
@@ -18,7 +18,7 @@ type Booking struct {
 	PhoneNumber    string
 	Email          string
 	Platform       string
-	ExternalId     string `gorm:"uniqueIndex:booking_external_id"`
+	ExternalId     *string `gorm:"uniqueIndex:booking_external_id"`
 	Items          []Item
 	Id             int
 	CustomerNumber int     `gorm:"column:customers"`
diff --git a/internal/booking/service.go b/internal/booking/service.go
index 0dd7ed1..cda8b4c 100644
--- a/internal/booking/service.go
+++ b/internal/booking/service.go
@@ -38,7 +38,7 @@ func (bs Service) All() []*Line {
 }
 
 func (bs Service) Create(From time.Time, To time.Time, Name string, PhoneNumber string, Email string, Platform string,
-	CustomerNumber int, PlatformFees float64, externalId string,
+	CustomerNumber int, PlatformFees float64, externalId *string,
 ) *Booking {
 	b := &Booking{
 		Name:           Name,
@@ -253,7 +253,7 @@ func (bs Service) ParseFromApi(rawContent string) (*Booking, error) {
 	standardRate := extractFloat(`Standard Rate\n\s+€ (\d+)`, content)
 	taxQty := (totalAmount - standardRate*float64(stayLength)) / 1.5
 
-	b := bs.Create(*formatDate(arrivalDate), *formatDate(departureDate), customerName, "", customerEmail, "Booking", customerNumber, commissionAmount, externalId)
+	b := bs.Create(*formatDate(arrivalDate), *formatDate(departureDate), customerName, "", customerEmail, "Booking", customerNumber, commissionAmount, &externalId)
 	bs.CreateItem(b.Id, item, stayLength, standardRate, "Card")
 	bs.CreateItem(b.Id, "Taxes", int(taxQty), 1.5, "Cash")
 
diff --git a/internal/server/handle_bookings.go b/internal/server/handle_bookings.go
index 2383688..1c6db05 100644
--- a/internal/server/handle_bookings.go
+++ b/internal/server/handle_bookings.go
@@ -72,7 +72,7 @@ func handleCreateBooking(bs *booking.Service) echo.HandlerFunc {
 		ts, _ = myTime.ParseFromForm(c.FormValue("to"))
 		nb.To = ts
 
-		b := bs.Create(nb.From, nb.To, nb.Name, nb.PhoneNumber, nb.Email, nb.Platform, nb.CustomerNumber, nb.PlatformFees, "") // TODO: add field in the form
+		b := bs.Create(nb.From, nb.To, nb.Name, nb.PhoneNumber, nb.Email, nb.Platform, nb.CustomerNumber, nb.PlatformFees, nil) // TODO: add field in the form
 		return c.Redirect(http.StatusSeeOther, fmt.Sprintf("%s/%d", constant.RouteBooking, b.Id))
 	}
 }