i keep getting the this error message whenever i do sudo apt-get update, any help please:

lamin@gudah:~$ sudo apt-get update
Reading package lists... Done
N: Ignoring file '50unattended-upgrades.ucf-dist' in directory '/etc/apt/apt.conf.d/' as it has an invalid filename extension
E: Could not get lock /var/lib/apt/lists/lock - open (11: Resource temporarily unavailable)
E: Unable to lock directory /var/lib/apt/lists/