SAC Analytic Application prompt values is not updating default bookmark

Hello Colleagues,

We have developed a tool on Analytic Application using BPC live connection. And we would like to update the variables from prompt using the variable values from another data source. Currently, I am using API :

After updating it is supposed to be updated in the prompt like:

But it gets back to old value after refreshing/reloading application.

Current workaround: Update the values every time oninitialization of the app but still sometimes it works and sometime doesn't. Currently, In modelling I can see the updated values whereas in Prod if I have a default bookmark saved then its showing the old values.
Is there any ongoing issue with the bookmark ?

Kindly support to resolve the issue.

Thank you.