Dynamic text - classic vs. optimized design

I have an issue when creating stories in SAC

Classic Design Experience - chart = numeric point, title replaced with dynamic text --> OK

Optimized Design Experience - chart = numeric point, want to replace title with dynamic text but I get a menu where the first section keeps loading (as if it cannot find the menu options).

Is there an issue (since recently) with the optimized design? Because I already created other stories where I had no issues adding dynamic text in the optimized design experience.

Kind regards,

Lieselot