Recheck exists after wait

app/src/main/java/eu/faircode/email/Core.java

@@ -1159,6 +1159,11 @@ class Core {
                     Log.w(ex);
                 }
             }
+
+            DB db = DB.getInstance(context);
+            message = db.message().getMessage(message.id);
+            if (message == null || message.uid != null)
+                return;
         }
 
         Message[] imessages = ifolder.search(new MessageIDTerm(message.msgid));