"ERROR: NVIDIA driver is not loaded" - Linux Mint 20 Ulyana

I have installed Linux Mint 20 Ulyana, with secure boot enabled, on my Mi Horizon 14 notebook equipped with Geforce MX350. After the installation I have enabled nvidia-driver-440 using Driver Manager. However, when I issue sudo nvidia-setttings in terminal I get the following error message.

ERROR: NVIDIA driver is not loaded
ERROR: Unable to load info from any available system.
(nvidia-settings:1702): GLib-GObject-CRITICAL **: 23:31:25.342: g_object_unref: assertion 'G_IS_OBJECT (object)' failed
** Message: 23:31:25.343: PRIME: No offloading required. Abort
** Message: 23:31:25.343: PRIME: is it supported? no

The output of nvidia-bug-report.sh can be found here if it helps to resolve this issue.

Update 1: Attaching the output of sudo modprobe nvidia

modprobe: ERROR: could not insert 'nvidia': Operation not permitted