list php error

Try resetting your page. Make a copy of your project if you have special changes made.

Impossible to answer without seeing your application.
I suggest to post your app to Demo Account and contact support directly.

The simplest solution is use the code PHPRunner already provides--
go to Events view for your ADD page for that Record form
Whatever page where you create the Form that saves that record go there in the Events view and
Select the "After Record added"
If you have Right-click activated on your mouse you can use it to bring up your options
from the pop up window that says "Select actions" select the last one offered under OTHER..
"Redirect to another page"
The result will be this piece of code deposited in the Events code view
header("Location: header.php?");

exit();
Modify it so that it points to the actual name of the list page for that record:
header("Location: my_list.php?");

exit();
Save it, build it, the updated list record will come.
Another tip would be to go to your "Edit SQL query" view on that Record table and make the first numeric id, the primary id, SORT Type = Descending.

Then you will see a '1' in the Sort Order column
SQL will show ORDER BY "your_id DESC"
That way every time you add a new record the LAST record added will show up at the Top of the list.
That little "header" code in Events will MAKE your list page update with the latest record sitting at the top, easy to view and confirm.