Nvidia drivers issue on ubuntu 18.04

base os : Windows 10
Dual boot with ubuntu 18.04
Previous graphics card: geforce 1080ti
Current graphics card: titan xp

My drivers are not getting recognised. Whenever i now run nvidia-smi
NVIDIA-SMI has failed because it couldn’t communicate with the NVIDIA driver. Make sure that the latest NVIDIA driver is installed and running.

Please help its really urgent

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