Invalid public key for CUDA apt repository

The invalid public key for the CUDA apt repository can be resolved by following these steps:

1. Open a terminal.
2. Run the following command to remove the existing CUDA repository key: sudo apt-key del <KEY_ID> Replace <KEY_ID> with the actual key ID of the CUDA repository key.
3. Run the following command to add the new CUDA repository key: sudo apt-key adv --fetch-keys https://developer.download.nvidia.com/compute/cuda/repos/ubuntu2004/x86_64/7fa2af80.pub
4. Update the package lists by running the following command: sudo apt update
5. Now, you should be able to install CUDA packages without any issues.

Note: Make sure you have the correct CUDA repository URL and key for your system.