Getting /sbin/ldconfig.real: "/usr/local/cuda-10.2/lib64" is not a known library type while installing cudnn8

I followed the installation guide on Installation Guide :: NVIDIA Deep Learning cuDNN Documentation
using the sudo dpkg -i libcudnn8_x.x.x-1+cudax.x_amd64.deb

I reinstalled cuda10.2 again to make sure everything is ok but i still run into the same problems.