diff --git a/user_channel/user_mgmt.cpp b/user_channel/user_mgmt.cpp
index 4ec61d5..97e6a8c 100644
--- a/user_channel/user_mgmt.cpp
+++ b/user_channel/user_mgmt.cpp
@@ -565,7 +565,7 @@
         return false;
     }
     if (!std::regex_match(userName.c_str(),
-                          std::regex("[a-zA-z_][a-zA-Z_0-9]*")))
+                          std::regex("[a-zA-Z_][a-zA-Z_0-9]*")))
     {
         log<level::ERR>("Unsupported characters in user name");
         return false;