Try to update Ubuntu from 18.04 to 18.10 then to 19.04

All right, it should be easy but it seems unusually difficult. I have an Ubuntu instance 18.04 (Bionic) AWS EC2 that I want to upgrade. I realize that I will have to do it in two stages, but I have some problems, as follows.

I did a lot of research on it, so here's what I did:

sudo rm / var / lib / ubuntu-release-upgrade / release-upgrade-available

Modified / etc / update-manager / release-upgrades and set Prompt = from lts to normal.

sudo apt update
sudo apt upgrade
sudo apt dist-upgrade

Tried: sudo do-release-upgrade
Result: Checking a new version of Ubuntu
Failed to connect to https://changelogs.ubuntu.com/meta-release. Check your Internet connection or your proxy settings
No new version found.

Tried: sudo do-release-upgrade -d
Result: Checking a new version of Ubuntu
Failed to connect to https://changelogs.ubuntu.com/meta-release-development. Check your Internet connection or your proxy settings
Upgrades of the development version are only
available from the latest supported version.

I can send to https://changelogs.ubuntu.com/meta-release-development without any problem.

I restarted the server a few times and I tried to repeat the process, without success. I even found an article that recommended

I suppose if 18.10 or 19.04 were registered as LTS, I would be able to upgrade them, but that does not help at the moment.

All ideas would be very appreciated. I would prefer not to create a new server at this point (although I have to convert the version to IaC later).

Thank you.