diff --git a/chat/anthropic.go b/chat/anthropic.go
index 8d79fdd..8ed89e6 100644
--- a/chat/anthropic.go
+++ b/chat/anthropic.go
@@ -2,6 +2,7 @@ package chat
 
 import (
 	"context"
+	"errors"
 	"fmt"
 	"github.com/kznrluk/aski/conv"
 	"github.com/kznrluk/go-anthropic"
@@ -47,6 +48,9 @@ func (a ap) rest(ctx context.Context, conv conv.Conversation) (string, error) {
 	)
 
 	if err != nil {
+		if errors.Is(err, context.Canceled) {
+			return "", ErrCancelled
+		}
 		return "", err
 	}
 	if len(rest.Content) == 0 {
@@ -70,6 +74,9 @@ func (a ap) stream(ctx context.Context, conv conv.Conversation) (string, error)
 	)
 
 	if err != nil {
+		if errors.Is(err, context.Canceled) {
+			return "", ErrCancelled
+		}
 		return "", err
 	}
 
@@ -79,6 +86,8 @@ func (a ap) stream(ctx context.Context, conv conv.Conversation) (string, error)
 		if err != nil {
 			if err == io.EOF {
 				break
+			} else if errors.Is(err, context.Canceled) {
+				return "", ErrCancelled
 			} else {
 				fmt.Printf("%s", err.Error())
 				return "", err
diff --git a/chat/chat.go b/chat/chat.go
index 12a282f..81fe132 100644
--- a/chat/chat.go
+++ b/chat/chat.go
@@ -2,6 +2,7 @@ package chat
 
 import (
 	"context"
+	"errors"
 	"github.com/kznrluk/aski/config"
 	"github.com/kznrluk/aski/conv"
 	"os"
@@ -18,6 +19,10 @@ type (
 	}
 )
 
+var (
+	ErrCancelled = errors.New("cancelled")
+)
+
 func ProvideChat(model string, cfg config.Config) Chat {
 	if strings.HasPrefix(model, "claude") {
 		return NewAnthropic(cfg.AnthropicAPIKey)
diff --git a/chat/openai.go b/chat/openai.go
index 4e436e0..0f4e551 100644
--- a/chat/openai.go
+++ b/chat/openai.go
@@ -2,6 +2,7 @@ package chat
 
 import (
 	"context"
+	"errors"
 	"fmt"
 	"github.com/kznrluk/aski/conv"
 	"github.com/sashabaranov/go-openai"
@@ -61,6 +62,9 @@ func (o oai) rest(ctx context.Context, conv conv.Conversation) (string, error) {
 	)
 
 	if err != nil {
+		if errors.Is(err, context.Canceled) {
+			return "", ErrCancelled
+		}
 		return "", err
 	}
 	fmt.Printf("%s", resp.Choices[0].Message.Content)
@@ -95,6 +99,9 @@ func (o oai) stream(ctx context.Context, conv conv.Conversation) (string, error)
 	)
 
 	if err != nil {
+		if errors.Is(err, context.Canceled) {
+			return "", ErrCancelled
+		}
 		return "", err
 	}
 
@@ -104,6 +111,8 @@ func (o oai) stream(ctx context.Context, conv conv.Conversation) (string, error)
 		if err != nil {
 			if err == io.EOF {
 				break
+			} else if errors.Is(err, context.Canceled) {
+				return "", ErrCancelled
 			} else {
 				return "", err
 			}
diff --git a/conv/conversation.go b/conv/conversation.go
index 43d25e9..93c70b5 100644
--- a/conv/conversation.go
+++ b/conv/conversation.go
@@ -131,6 +131,13 @@ func (c *conv) ChangeHead(sha1Partial string) (Message, error) {
 	foundSha := false
 	foundMessageIndex := -1
 
+	if sha1Partial == "ROOT" {
+		for i := range c.Messages {
+			c.Messages[i].Head = false
+		}
+		return c.convertSystemToMessage(), nil
+	}
+
 	for i, message := range c.Messages {
 		if strings.HasPrefix(message.Sha1, sha1Partial) {
 			foundSha = true
diff --git a/lib/dialog.go b/lib/dialog.go
index a3c73e4..afab202 100644
--- a/lib/dialog.go
+++ b/lib/dialog.go
@@ -2,6 +2,7 @@ package lib
 
 import (
 	"context"
+	"errors"
 	"fmt"
 	"github.com/fatih/color"
 	"github.com/kznrluk/aski/chat"
@@ -100,6 +101,10 @@ func StartDialog(cfg config.Config, cv conv.Conversation, isRestMode bool, resto
 		fmt.Printf("\n")
 		data, err := cli.Retrieve(cv, isRestMode)
 		if err != nil {
+			if errors.Is(err, chat.ErrCancelled) {
+				_, _ = cv.ChangeHead(last.ParentSha1)
+				continue
+			}
 			fmt.Printf("\n%s", err.Error())
 			continue
 		}