diff --git a/db/bill.ts b/db/bill.ts
index 76f054b..2a91f19 100644
--- a/db/bill.ts
+++ b/db/bill.ts
@@ -87,5 +87,5 @@ BillSchema.virtual('total').get(function (): number {
   return getBillTotal(bill)
 })
 
-export default <BillModel>mongoose.models.Bill ||
-  mongoose.model<BillDocument, BillModel>('Bill', BillSchema)
+export default (mongoose.models.Bill ||
+  mongoose.model<BillDocument, BillModel>('Bill', BillSchema)) as BillModel
diff --git a/db/booking.ts b/db/booking.ts
index 31fb893..11a8d61 100644
--- a/db/booking.ts
+++ b/db/booking.ts
@@ -143,5 +143,5 @@ BookingSchema.static('findBookedDays', async function (
     .sort()
 })
 
-export default <BookingModel>mongoose.models.Booking ||
-  mongoose.model<BookingDocument, BookingModel>('Booking', BookingSchema)
+export default (mongoose.models.Booking ||
+  mongoose.model<BookingDocument, BookingModel>('Booking', BookingSchema)) as BookingModel