diff --git a/utils/verify_code.go b/utils/verify_code.go
index 7f3d7c4..e9de009 100644
--- a/utils/verify_code.go
+++ b/utils/verify_code.go
@@ -6,7 +6,7 @@ import (
 	"unsafe"
 )
 
-const letters = "abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ"
+const letters = "abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ1234567890"
 
 var src = rand.NewSource(time.Now().UnixNano())