This is as intended. Since saving is not possible during a cutscene, the default Pause menu's Save button will be hidden automatically when opened while in one.
You can bypass this behaviour by renaming your Pause menu's "SaveButton" element to something else (e.g. "_SaveButton"), but the user will not be able to save the game while in a cutscene.
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Welcome to the community, @CKJAX.
This is as intended. Since saving is not possible during a cutscene, the default Pause menu's Save button will be hidden automatically when opened while in one.
You can bypass this behaviour by renaming your Pause menu's "SaveButton" element to something else (e.g. "_SaveButton"), but the user will not be able to save the game while in a cutscene.