Passing flag from PF_Cmd_USER_CHANGED_PARAM to PF_Cmd_UPDATE_PARAMS_UI

Dear AE fellows,
I have the following strange behavior.
I set some parameter in PF_Cmd_USER_CHANGED_PARAM function.
After this, the PF_Cmd_UPDATE_PARAMS_UI call immediately triggered.
However, the flag as well as the value of this parameter is not passed correctly.

For example, flag set in the PF_Cmd_USER_CHANGED_PARAM function should be: supervise + collapsed. When entering the PF_Cmd_UPDATE_PARAMS_UI function only supervise flag survived (it is set initially in Global set up).
Also, I change the parameter value in PF_Cmd_USER_CHANGED_PARAM (set it to zero).
However, when entering PF_Cmd_UPDATE_PARAMS_UI it is value is inherited from the previous user value (not set to zero).
What shall I change?

Yaroslav.