diff --git a/kernel/model/conf.go b/kernel/model/conf.go
index 237dce979..fc3416363 100644
--- a/kernel/model/conf.go
+++ b/kernel/model/conf.go
@@ -1008,8 +1008,6 @@ func IsSubscriber() bool {
 }
 
 func IsPaidUser() bool {
-	// S3/WebDAV data sync and backup are available for a fee https://github.com/siyuan-note/siyuan/issues/8780
-
 	if IsSubscriber() {
 		return true
 	}
diff --git a/kernel/model/sync.go b/kernel/model/sync.go
index b25eac3f3..7a61b2934 100644
--- a/kernel/model/sync.go
+++ b/kernel/model/sync.go
@@ -250,10 +250,14 @@ func checkSync(boot, exit, byHand bool) bool {
 	switch Conf.Sync.Provider {
 	case conf.ProviderSiYuan:
 		if !IsSubscriber() {
+			Conf.Sync.Enabled = false
+			Conf.Save()
 			return false
 		}
 	case conf.ProviderWebDAV, conf.ProviderS3, conf.ProviderLocal:
 		if !IsPaidUser() {
+			Conf.Sync.Enabled = false
+			Conf.Save()
 			return false
 		}
 	}