Unable to install Nginx my Ubuntu 18.04.3

I am a newcomer to setting up servers and can’t seem to install nginx on my Ubuntu 18.04.3 (LTS) x64 server from Digitalocean. I’ve tried reading other entries but none of the solutions seem to work for me. I have tried uninstalling and reinstalling but always get this same response.

sudo apt-get install nginx
Reading package lists... Done
Building dependency tree       
Reading state information... Done
Some packages could not be installed. This may mean that you have
requested an impossible situation or if you are using the unstable
distribution that some required packages have not yet been created
or been moved out of Incoming.
The following information may help to resolve the situation:

The following packages have unmet dependencies:
 nginx : Depends: nginx-core (< 1.14.0-0ubuntu1.7.1~) but it is not going to be installed or
                  nginx-full (< 1.14.0-0ubuntu1.7.1~) but it is not going to be installed or
                  nginx-light (< 1.14.0-0ubuntu1.7.1~) but it is not going to be installed or
                  nginx-extras (< 1.14.0-0ubuntu1.7.1~) but it is not going to be installed
         Depends: nginx-core (>= 1.14.0-0ubuntu1.7) but it is not going to be installed or
                  nginx-full (>= 1.14.0-0ubuntu1.7) but it is not going to be installed or
                  nginx-light (>= 1.14.0-0ubuntu1.7) but it is not going to be installed or
                  nginx-extras (>= 1.14.0-0ubuntu1.7) but it is not going to be installed
E: Unable to correct problems, you have held broken packages.

Any help would be greatly appreciated!