Deserialization

Hi @Niall during process create i set variables in map and used mariadb. previously i used key channel and his value channelref but now i used same key but value object changed like List that means i have two different object of same key but problem is came fetch all process from db(deserialization)
error:-org.camunda.bpm.engine.ProcessEngineException: Cannot deserialize object in variable ‘processChannel’: SPIN/JACKSON-JSON-01007 Cannot construct java type from string ‘java.util.ArrayList<com.orange.bos.ordercapture.dto.ChannelRef>’

current code:-
final List channelRefList = new ArrayList<>();
channelRefList.add(processRequest.getChannel());
variables.put(ProcessConstants.CHANNEL, Variables.objectValue(channelRefList)
.serializationDataFormat(Variables.SerializationDataFormats.JAVA).create());
final List systemList = new ArrayList<>();

previouse code:-’
ChannelRef channelRefList=new ChannelRef ();
channelRefList.add(processRequest.getChannel());
variables.put(ProcessConstants.CHANNEL, channelRefList
.serializationDataFormat(Variables.SerializationDataFormats.JAVA).create());
final channelRefList =new ChannelRef ();