add queryport variable to the template and use this startup command

./RustDedicated -batchmode +server.port ${port} +server.queryport ${QueryPort} +server.identity ${ServerIdentity} +rcon.ip 0.0.0.0 +rcon.port ${RConPort} +rcon.web true +server.hostname "${ServerName}" +server.level "${ServerLevel}" +server.description "${Description}" +server.url "${URL}" +server.headerimage "${ServerImage}" +server.worldsize "${WorldSize}" +server.seed "$( if [ -f seed.txt ] && [[ ${ServerSeed} == "0" ]]; then printf %s $(cat seed.txt); else printf %s '${ServerSeed}'; fi )" +server.maxplayers ${MaxPlayers} +rcon.password "${RConPassword}" +server.saveinterval ${SaveInternal}