GPU card/device is not being detected

My system is not detecting GPU(Nvidia RTX 2080ti 11GB) when I am trying to train ML models. commands I tried -

command: nvidia-smi
response: "NVIDIA-SMI has failed because it couldn’t communicate with the NVIDIA driver. Make sure that the latest NVIDIA driver is installed and running."

command: nvidia-settings
response: "Unable to init server: Could not connect: Connection refused
ERROR: The control display is undefined; please run nvidia-settings --help for usage information."

command: lspci
response: shows list of devices other than “nvidia gpu cards”

when I try to install Nvidia driver again, the following message is shown -

Not sure if the issue is from the software side or the hardware side. Would appreciate any help in fixing this issue.