Hello mariap,
Can you provide an OML to us to take a look?
This is probably a small problem in the logic, or something related to the refresh, but unless someone had this exactly same problem and knows the cause (I never had this problem), only looking to an example we will be able to help.
The example can be a simpler one. Also, sometimes, when we try to reproduce the error we find the solution :)
Cheers,
Eduardo Jauch