VServer not responding to command?

I have a VServer on which I would like to install Minecraft. There I want to install the version Spigot 1.8.8.

However, when I enter the start command for Start.sh, the program does not start.

If I want to start you, I get the following statement:

root @: / home / Minecraft / CityBuild # ./start.sh

./start.sh: line 1: screen: command not found

I have the following Java version on the server:
openjdk version "1.8.0_232"

OpenJDK Runtime Environment (AdoptOpenJDK) (build 1.8.0_232-b09)

OpenJDK 64-Bit Server VM (AdoptOpenJDK) (build 25.232-b09, mixed mode)

Tried a lot, but it just doesn't work.

Would love to stay with version 1.8.8.

Have to do the following on the vServer beforehand:

apt-get install screen

Ok thought it was already on it, but I have done it again.