Software Updater update failed

Question

When I'm trying to update all packages in my environment, using GUI or from terminal by :

sudo apt-get update

I get :

It simple says :

...
Err:19 http://ppa.launchpad.net/beineri/opt-qt-5.11.1-xenial/ubuntu bionic Release
  404  Not Found [IP: 91.189.95.85 80]
...

Using the GUI, I get :

But it exists : http://ppa.launchpad.net/beineri/opt-qt-5.11.1-xenial/ubuntu/

Answer 1

yes, the ppa exist but it "supports" until Ubuntu Xenial, while you're on bionic, so it will never work