diff --git a/cmd/lotus-storage-miner/market.go b/cmd/lotus-storage-miner/market.go
index 0e7be3dd3f5..6e3743143a9 100644
--- a/cmd/lotus-storage-miner/market.go
+++ b/cmd/lotus-storage-miner/market.go
@@ -164,12 +164,6 @@ var setAskCmd = &cli.Command{
 			Usage:    "Set the price of the ask for verified deals (specified as attoFIL / GiB / Epoch) to `PRICE`",
 			Required: true,
 		},
-		&cli.StringFlag{
-			Name:        "duration",
-			Usage:       "Set duration of ask (a quantity of time after which the ask expires) `DURATION`",
-			DefaultText: "720h0m0s",
-			Value:       "720h0m0s",
-		},
 		&cli.StringFlag{
 			Name:        "min-piece-size",
 			Usage:       "Set minimum piece size (w/bit-padding, in bytes) in ask to `SIZE`",
@@ -194,7 +188,7 @@ var setAskCmd = &cli.Command{
 		pri := types.NewInt(cctx.Uint64("price"))
 		vpri := types.NewInt(cctx.Uint64("verified-price"))
 
-		dur, err := time.ParseDuration(cctx.String("duration"))
+		dur, err := time.ParseDuration("720h0m0s")
 		if err != nil {
 			return xerrors.Errorf("cannot parse duration: %w", err)
 		}