WLS error crash instance

Hi,

after error on instance PD, we restart services

log: ####<Aug 19, 2021 11:46:17 AM ART> <Warning> <JMX> <ORACLE.subnetproduccio.oraclevcn.com> <AdminServer> <[ACTIVE] ExecuteThread: '16' for queue: 'weblogic.kernel.Default (self-tuning)'> <<WLS Kernel>> <> <> <1629384377674> <BEA-149535> <JMX Resiliency Activity Server=ORACLE_9666_ws06p : 
 Received a DISCONNECT EVENT 
> 
####<Aug 19, 2021 11:46:18 AM ART> <Error> <IIOP> <ORACLE.subnetproduccio.vncproduccion.oraclevcn.com> <AdminServer> <[ACTIVE] ExecuteThread: '18' for queue: 'weblogic.kernel.Default (self-tuning)'> <<WLS Kernel>> <> <> <1629384378028> <BEA-002012> <Failed to send exception class javax.management.remote.JMXServerErrorException: java.rmi.MarshalException: IOException while sending; nested exception is: 
    java.io.EOFException: Attempt to send message on closed socket.
java.rmi.MarshalException: IOException while sending; nested exception is: 
    java.io.EOFException: Attempt to send message on closed