diff --git a/main.go b/main.go
index fe1d8da..a6dd024 100644
--- a/main.go
+++ b/main.go
@@ -37,7 +37,7 @@ func main() {
 
 	// Setup openai store. TODO: make configurable
 	ttl := int64(24 * time.Hour) // 1 day
-	maxHistory := 10             // store only 10
+	maxHistory := 20             // store only 10
 
 	store := openai.NewStore(ttl, maxHistory)
 
diff --git a/pkg/openai/respond.go b/pkg/openai/respond.go
index bcfcfe9..d4e60f8 100644
--- a/pkg/openai/respond.go
+++ b/pkg/openai/respond.go
@@ -135,9 +135,10 @@ func (r *Responder) Respond(interactionKey string, prompts []ChatCompletionMessa
 
 	prompts = append(prompts, msgsRecv...)
 
-	// if cache size is greater than 10, remove the oldest message
+	// if cache size is greater than maxHistory, remove the oldest message
+	// but keep the first message as that is the pre-prompt
 	if len(prompts) > r.store.maxHistory {
-		prompts = prompts[1:]
+		prompts = append(prompts[:1], prompts[2:]...)
 	}
 
 	r.store.Set(interactionKey, prompts)