update msg

src/translations/en.json

@@ -165,7 +165,7 @@
   "loginErrorMessage4":"System Connection Failed",
   "loginErrorMessage5":"Incorrect Username or Password",
   "loginErrorMessage6":"User account not found",
-  "loginErrorMessage7":"System is under maintenance, please check back later",
+  "loginErrorMessage7":"System is under maintenance, please check back later.",
 
   "pleaseLloginMessage1":"User account already created",
   "pleaseLloginMessage2":"You are our existing user, please login to your account.",