Update Insight Custom field => cannot be cast to java.util.Collection' - groovy

Question

I have a strange problem. My script is practically finished.
To understand the script : In Insight, I have all our servers object created automatically.
We use a monitoring called Centreon, this monitoring send an email to the service desk mailbox automatically when a error occur and a ticket is created. I want to add the corresponding object to the corresponding server.
The name of the server is present in the summary of the email;
Example : AFDAOS.xxx.int problem alert
A groovy script check the name of the server, if it found a correspond name (in the FQDN Attribute), the object is affected to the ticket.
All code working until the updating of the ticket, i have a statement where all objects are checked, when i found the good object (string currentobject), i want to update the current issue with this object i have the error :
GroovyInsightException: com.riadalabs.jira.plugins.insight.services.model.ObjectBean cannot be cast to java.util.Collection'
BUT if I replace currentobject by Objects (I suppose it's an array), the ticket is updating with all objects without any error. I understand that I can only update the ticket with an array and not a unique value... I don't found the good way to do it... Thank you for your help.
import com.atlassian.jira.component.ComponentAccessor
import com.atlassian.jira.issue.fields.CustomField
import com.riadalabs.jira.plugins.insight.services.model.CommentBean;
import com.atlassian.jira.issue.MutableIssue
import com.atlassian.jira.event.type.EventDispatchOption
import com.riadalabs.jira.plugins.insight.channel.external.api.facade.ObjectFacade
import com.riadalabs.jira.plugins.insight.services.model.ObjectAttributeBean
import com.riadalabs.jira.plugins.insight.services.model.ObjectBean
import groovy.transform.ToString
Class objectFacadeClass = ComponentAccessor.getPluginAccessor().getClassLoader().findClass("com.riadalabs.jira.plugins.insight.channel.external.api.facade.ObjectFacade");
def objectFacade = ComponentAccessor.getOSGiComponentInstanceOfType(objectFacadeClass);
//CustomField jiraCustomField = ComponentAccessor.getCustomFieldManager().getCustomFieldObject(12124);
CustomField insightCF = ComponentAccessor.getCustomFieldManager().getCustomFieldObject(12124);
Class iqlFacadeClass = ComponentAccessor.getPluginAccessor().getClassLoader().findClass("com.riadalabs.jira.plugins.insight.channel.external.api.facade.IQLFacade");
def iqlFacade = ComponentAccessor.getOSGiComponentInstanceOfType(iqlFacadeClass);
def objects = iqlFacade.findObjectsByIQLAndSchema(10,"objectTypeId = 2443");
//def test = "AF-172738"
//def ObjectInsightBean = objectFacade.loadObjectBean(test)
//log.warn("ObjectInsightBean " + ObjectInsightBean)
def n = 0
(objects).each {
CurrentObject = objects[n]
def fqdnvalue = objectFacade.loadObjectAttributeBean(CurrentObject.getId(),47464).getObjectAttributeValueBeans()[0]; //Load Attribute Value
def fqdn_string = fqdnvalue.toString()
def fqdn_string_split = fqdn_string.split("\\(");
def fqdn_string_split_1 = fqdn_string_split[1]
def fqdn_string_split_2 = fqdn_string_split_1.substring(0, fqdn_string_split_1.length() - 2);
result = (issue.getSummary().contains(fqdn_string_split_2)) // if the value fqdn_string_split_2 present in the summary => result = true
if (result==true){
log.info("Statement " + "True" + CurrentObject);
MutableIssue mi = (MutableIssue) issue;
mi.setCustomFieldValue(insightCF, CurrentObject); // => Work if i replace CurrentObject by objects
ComponentAccessor.getIssueManager().updateIssue(currentUser, mi, EventDispatchOption.DO_NOT_DISPATCH, false); // Error GroovyInsightException: com.riadalabs.jira.plugins.insight.services.model.ObjectBean cannot be cast to java.util.Collection'
}
log.info("fqdn_string_split_2 " + fqdn_string_split_2)
log.info("Result " + result)
n ++
return result;
}
Solved by converting the string into List:
if (result==true){
//log.info("Statement " + "True" + CurrentObject);
MutableIssue mi = (MutableIssue) issue;
def CurrentObject_list = [CurrentObject];
log.info("List " + CurrentObject_list);
mi.setCustomFieldValue(insightCF, CurrentObject_list); // => Work if i replace CurrentObject by objects
ComponentAccessor.getIssueManager().updateIssue(currentUser, mi, EventDispatchOption.DO_NOT_DISPATCH, false); // Error GroovyInsightException: com.riadalabs.jira.plugins.insight.services.model.ObjectBean cannot be cast to java.util.Collection'
}
//log.info("fqdn_string_split_2 " + fqdn_string_split_2)
//log.info("Result " + result)
n ++
return result;