diff --git a/timing/rob/rob.go b/timing/rob/rob.go
index e62925fb..3d0e41db 100644
--- a/timing/rob/rob.go
+++ b/timing/rob/rob.go
@@ -34,7 +34,6 @@ type ReorderBuffer struct {
 	hooks map[*sim.HookPos][]sim.Hook
 }
 
-
 func (b *ReorderBuffer) getTaskID() string {
     if b.transactions.Len() > 0 {
         trans := b.transactions.Front().Value.(*transaction)
@@ -57,7 +56,7 @@ func (b *ReorderBuffer) Tick() (madeProgress bool) {
 	if !b.isFlushing {
 		madeProgress = b.runPipeline() || madeProgress
 	}
-	// b.ExportMilestonesToCSV("../samples/fir/milestones.csv")
+
 	return madeProgress
 }
 
@@ -148,28 +147,18 @@ func (b *ReorderBuffer) runPipeline() (madeProgress bool) {
 	return madeProgress
 }
 
-<<<<<<< HEAD
-func (b *ReorderBuffer) topDown(now sim.VTimeInSec) bool {
+func (b *ReorderBuffer) topDown() bool {
     if b.isFull() {
 		tracing.AddMilestone(
 			b.getTaskID(),
 			"Hardware Occupancy",
 			"Buffer full",
 			"topDown",
-			now,
 			b,
 		)
         return false
     }
-	item := b.topPort.Peek()
-=======
-func (b *ReorderBuffer) topDown() bool {
-	if b.isFull() {
-		return false
-	}
-
 	item := b.topPort.PeekIncoming()
->>>>>>> origin/v4
 	if item == nil {
 		return false
 	}
@@ -179,18 +168,19 @@ func (b *ReorderBuffer) topDown() bool {
 
 	trans.reqToBottom.Meta().Src = b.bottomPort
 	err := b.bottomPort.Send(trans.reqToBottom)
+	if err != nil {
+		return false
+	}
     if err != nil {
         tracing.AddMilestone(
             b.getTaskID(),
             "Network Error",
             "Unable to send request to bottom port",
             "topDown",
-            now,
 			b,
         )
         return false
     }
-	
 	b.addTransaction(trans)
 	b.topPort.RetrieveIncoming()
 
@@ -201,29 +191,19 @@ func (b *ReorderBuffer) topDown() bool {
 	return true
 }
 
-<<<<<<< HEAD
-func (b *ReorderBuffer) parseBottom(now sim.VTimeInSec) bool {
-	item := b.bottomPort.Peek()
+func (b *ReorderBuffer) parseBottom() bool {
+	item := b.bottomPort.PeekIncoming()
     if item == nil {
         tracing.AddMilestone(
             b.getTaskID(),
             "Dependency",
             "Waiting for bottom response",
             "parseBottom",
-            now,
 			b,
         )
         return false
     }
 
-=======
-func (b *ReorderBuffer) parseBottom() bool {
-	item := b.bottomPort.PeekIncoming()
-	if item == nil {
-		return false
-	}
->>>>>>> origin/v4
-
 	rsp := item.(mem.AccessRsp)
 	rspTo := rsp.GetRspTo()
 	transElement, found := b.toBottomReqIDToTransactionTable[rspTo]
@@ -242,13 +222,12 @@ func (b *ReorderBuffer) parseBottom() bool {
 
 func (b *ReorderBuffer) bottomUp() bool {
 	elem := b.transactions.Front()
-    if elem == nil {
+	if elem == nil {
         tracing.AddMilestone(
             b.getTaskID(),
             "Dependency",
             "No transactions to process",
             "bottomUp",
-            now,
 			b,
         )
         return false
@@ -261,7 +240,6 @@ func (b *ReorderBuffer) bottomUp() bool {
             "Dependency",
             "Waiting for bottom response",
             "bottomUp",
-            now,
 			b,
         )
 		return false
@@ -272,17 +250,9 @@ func (b *ReorderBuffer) bottomUp() bool {
 	rsp.Meta().Src = b.topPort
 
 	err := b.topPort.Send(rsp)
-    if err != nil {
-        tracing.AddMilestone(
-            b.getTaskID(),
-            "Network Error",
-            "Unable to send request to bottom port",
-            "bottomUp",
-            now,
-			b,
-        )
-        return false
-    }
+	if err != nil {
+		return false
+	}
 
 	b.deleteTransaction(elem)
 
@@ -374,41 +344,4 @@ func (b *ReorderBuffer) duplicateWriteDoneRsp(
 	return mem.WriteDoneRspBuilder{}.
 		WithRspTo(rspTo).
 		Build()
-}
-
-func ExportMilestonesToCSV(filename string) error {
-    milestones := tracing.GetAllMilestones()
-
-    file, err := os.Create(filename)
-    if err != nil {
-        return err
-    }
-    defer file.Close()
-
-    writer := csv.NewWriter(file)
-    defer writer.Flush()
-
-    headers := []string{"ID", "TaskID", "BlockingCategory", "BlockingReason", "BlockingLocation", "Timestamp"}
-    if err := writer.Write(headers); err != nil {
-        return err
-    }
-
-    for _, m := range milestones {
-        fmt.Printf("ID: %s, TaskID: %s, Category: %s, Reason: %s, Location: %s, Timestamp: %v\n",
-            m.ID, m.TaskID, m.BlockingCategory, m.BlockingReason, m.BlockingLocation, m.Timestamp)
-        record := []string{
-            m.ID,
-            m.TaskID,
-            m.BlockingCategory,
-            m.BlockingReason,
-            m.BlockingLocation,
-            fmt.Sprintf("%v", m.Timestamp),
-        }
-        if err := writer.Write(record); err != nil {
-            return err
-        }
-    }
-
-    return nil
-}
-
+}
\ No newline at end of file
diff --git a/timing/rob/rob_test.go b/timing/rob/rob_test.go
index f0e16d14..d6cfda19 100644
--- a/timing/rob/rob_test.go
+++ b/timing/rob/rob_test.go
@@ -7,6 +7,7 @@ import (
 	. "github.com/onsi/gomega"
 	"github.com/sarchlab/akita/v4/mem/mem"
 	"github.com/sarchlab/akita/v4/sim"
+	"github.com/sarchlab/akita/v4/tracing"
 )
 
 type myHook struct {
@@ -43,8 +44,8 @@ var _ = Describe("Reorder Buffer", func() {
 		rob.AddHook(tracing.HookPosMilestone, &myHook{
 			f: func(ctx sim.HookCtx) {
 				milestone := ctx.Item.(tracing.Milestone)
-				fmt.Printf("Milestone in test: ID=%s, TaskID=%s, Category=%s, Reason=%s, Location=%s, Timestamp=%v\n",
-					milestone.ID, milestone.TaskID, milestone.BlockingCategory, milestone.BlockingReason, milestone.BlockingLocation, milestone.Timestamp)
+				fmt.Printf("Milestone in test: ID=%s, TaskID=%s, Category=%s, Reason=%s, Location=%s\n",
+					milestone.ID, milestone.TaskID, milestone.BlockingCategory, milestone.BlockingReason, milestone.BlockingLocation)
 			},
 		})