Your Lyrics contain Copyrighted material

https://preview.redd.it/ic4dzvtjrqoh1.png?width=446&format=png&auto=webp&s=e6ed4cc525f18d53499eb8175fbd2ae4845b1e06

The copyrighted material;
Duhh duh duuh duhh duh

I.e. if it is in the lyrics box, it doesn't allow me to generate, if i remove it, it generates the song.
I have tried certain variations.

How can someone copyright "Duhh duh duuh duhh duh"? (or variations of it)
Only yesterday, working on the same song, it freely allowed me to generate it with those "lyrics".
Now, it doesn't.