STM32G461 Support?

Hello,
we use µVision 5.20.0.0 (armgcc V5.06).
We have difficulties to run the debugger using the STM32G491.
The project can be compiled and then flashed on the contoller (verified by the ST32CubeProgrammer).
But the debugger doesn't show any progress.

Any suggestions, questions or proposed solutions?

Thank you!