Installing 3cx onto Lightsail, no 5001 checkbox

[vk4kij]

Trying to install a 3cx instance on AWS Lightsail.

The first time I did it I had a checkbox to tick for using port 5001.

I did not check it, but realised I did want it for the web interface.

I removed the instance from AWS Lightsail and have tried to re-install, but the checkbox now no longer comes up.

Thanks.

Ian.