Hi Mikkie
What version of Questa are you using?
With 2024.2 I turned on VHDL-2019. The features work fine, but in 2025.1 Questa decided to throw warnings for this feature.
If it is not 2025.1, then it is probably too old like 10.4 or 10.5.
I have been running regressions with 2024.3_1.
Best Regards
Jim