You approach is wrong. Jellyfin has a special metadata field for CUSTOM parental control, you should use it instead to avoid headaches.
On any contain, click the 3 dots and then "Edit Metadata". Scroll down and find "Parental Rating". This one is the official parental rating that is grabbed online (imdb, tvdb, etc....). Its not always populated, or its not always correct to your own tastes.
That's precisely why, beside it, you have "Custom rating". Adapt that one and it will never move, never be deleted or changed, and it will always take precedence over the official rating..
Also by using the rating classification in the list of choices (All, 6, 12, 14, 16...) you only do the job once instead of changing kid1, to kid2, to kid3 for everything as your kid grow up. You just have to edit your kid account and define which age rating stuff he can see.
On any contain, click the 3 dots and then "Edit Metadata". Scroll down and find "Parental Rating". This one is the official parental rating that is grabbed online (imdb, tvdb, etc....). Its not always populated, or its not always correct to your own tastes.
That's precisely why, beside it, you have "Custom rating". Adapt that one and it will never move, never be deleted or changed, and it will always take precedence over the official rating..
Also by using the rating classification in the list of choices (All, 6, 12, 14, 16...) you only do the job once instead of changing kid1, to kid2, to kid3 for everything as your kid grow up. You just have to edit your kid account and define which age rating stuff he can see.