The server was told to stop
What it looks like in your log
Minecraft server exited with code 143
What causes it
Exit code 143 means the process received a stop signal, normally from the panel or host during a restart or a shutdown that overran its time budget.
How to fix it
Nothing to fix if you stopped it on purpose. If it happens on its own, something is hanging the shutdown (world saving, a slow plugin); check what runs right before it.
Not sure this is your problem? Paste your log and Roastd will tell you which of these it actually matched, and what else it found.
Check your own log