Error while import PAR with schedule task

Hi everybody

I've the following error while import a new PAR with schedule task in Portal NW04s

Inner Stack is:

Unable to lock the local configuration to run import "import_it.tsf.pld.cercapersone.updateadgruppofs.st.prjconfig_config_fwk_service_4692550,4692550_(ready)".

System error is "LockConfigException: Configuration framework system error: "configuration-lock-service overloaded: cannot acquire central-lock file for config://local"".

Inner Stack is:

LockConfigException: Configuration framework system error: "configuration-lock-service overloaded: cannot acquire central-lock file for config://local"

at com.sapportals.config.fwk.data.ConfigLockManager.lockWithDependent(ConfigLockManager.java:507)

thanks in advance