I think this is not really an error, you are just not aware (misunderstanding) that hashcat 6.0.0 and above recommend using CUDA.
I'm not sure if your "professional" GPU supports it (I pretty much would assume so, otherwise it wouldn't make sense to buy these professional cards that are mostly used in some datacenters - or of course a few years ago in mining rigs etc - and by cloud providers etc, but of course there are exceptions). Download CUDA from https://developer.nvidia.com/cuda-downloads and the warning message will disappear if you correclty installed it.
I'm not sure if your "professional" GPU supports it (I pretty much would assume so, otherwise it wouldn't make sense to buy these professional cards that are mostly used in some datacenters - or of course a few years ago in mining rigs etc - and by cloud providers etc, but of course there are exceptions). Download CUDA from https://developer.nvidia.com/cuda-downloads and the warning message will disappear if you correclty installed it.