I've got two input sources in my Language & Region's Keyboard settings. Dutch and English.
Dutch ('Nederlands') being my default language. Every now and then however, when I startup my Mac, the Dutch input source has disappeared and only the US English one ('VS') is present. So I have to add Dutch as the input source again.
Why does it do that and how can I lock my input sources in place? I've tried deleting the VS one, leaving only Nederlands as an input source, but it has also happened at some time that the Nederlands one disappeared nevertheless and the VS one reappeared by itself.

Dutch ('Nederlands') being my default language. Every now and then however, when I startup my Mac, the Dutch input source has disappeared and only the US English one ('VS') is present. So I have to add Dutch as the input source again.
Why does it do that and how can I lock my input sources in place? I've tried deleting the VS one, leaving only Nederlands as an input source, but it has also happened at some time that the Nederlands one disappeared nevertheless and the VS one reappeared by itself.