apt dont want to "Update" the Simutrans DEB Repo

[NNW]

Hello
I get an apt update error for the Simutrans DEB repo: E:The repository 'https://simutrans-germany.com/simutrans/linux-package/deb/debian lenny Release' does not have a Release file.
So what is wrong with this repo and how can i fix this?

[captain crunch]

Their TLS certificate probably is not known or trusted by your computer. You can check this by entering the following command in a shell:

Code Select Expand

curl -I https://simutrans-germany.com/simutrans/linux-package/deb/debian

[NNW]

Code Select Expand

HTTP/1.1 301 Moved Permanently
Date: Sat, 14 Dec 2019 09:20:15 GMT
Server: Apache
Location: https://simutrans-germany.com/simutrans/linux-package/deb/debian/
Vary: Accept-Encoding
Content-Type: text/html; charset=iso-8859-1

Ok, and now, what to do?

[Ters]

The theory that the certificate isn't trusted seems disproved. Maybe you simply lack the missing slash. That it should be https://simutrans-germany.com/simutrans/linux-package/deb/debian/ not https://simutrans-germany.com/simutrans/linux-package/deb/debian

[NNW]

No. Same error.
I have deleted the Entry for the Repo.
Seems, that LM 19 dont like it.