Installing GDAL on Ubuntu 20.04 - unmet dependencies

I’m trying to install GDAL on my Ubuntu 20.04 with the following commands:

sudo add-apt-repository ppa:ubuntugis/ppa && sudo apt-get update
sudo apt-get update
sudo apt-get install gdal-bin
sudo apt-get install libgdal-dev

After running the last line, I get the following error:

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:
 libgdal-dev : Depends: libpq-dev but it is not going to be installed
E: Unable to correct problems, you have held broken packages.

What is the problem here?