You are attempting to select and make use of the Oracle Intelligent policy. The Specify backup file name formats is checked by no change is made to the formats. When you Apply the changes, come out of the policy and then go back in, the check box is unchecked.
The bppllist output will also not reflect the changes.
This is by design, when the box is not checked the greyed out values are the default. these are the values which will be used if you do nothing. You check the box to override the default values.
Note: If you do modify the formats, NetBackup validates them so they have to end with a %t. If they do not, the modification is rejected and a pop-up window is displayed explaining the %t is required and the changes were not saved.