After de-installing Matomo, I cannot re-install

I installed Matomo on a subdomain using Spectaculous. Everything went fine, but I forgot to write down the Admin name (…stupid I know). I then uninstalled it according to the instructions in the link given below. The was no issue removing all the files or deleting the DB. When I used Spectaculous to re-install it I got this message" * An installation already exists at as per our records. To re-install the application please uninstall the existing installation!". There is nothing left to delete, so how can I re-install?

Kind regards

How do I uninstall Matomo? FAQ - Analytics Platform - Matomo

I don’t know Spectaculous. I imagine it is some server administration tool.
Maybe the HTTP port, website or anything else about Matomo existence is still present in the Spectaculous records… ?

Spectaculous is a PHP installer in some hosting providers the automatically carries out all the deployment steps. Your suggestion was spot on - there is an installation overview for each software package, and it is there that the deinstallation is controlled. The list of installations was off the bottom of the screen, so I missed it…
Many thanks for your comments!