Open the <OIM_HOME>/server/config/cache.ccf" file and make sure the default auxiliary is set to LTCP for every region as given below.

jcs.default=LTCP

jcs.region.DataObjectEventHandlers=LTCP

jcs.region.ProcessDefinition=LTCP

At the end of the cache.ccf file, keep all default LTCP settings as explained in the "Configuration" section of JCS doc https://commons.apache.org/proper/commons-jcs/LateralUDPDiscovery.html unless you need to change based on your requirements.