icontrol error on 1 special irule and request

When I collect via icontrol (11.3 and 11.6) information about 1 specific irule than I get the following error:

 

System.Web.Services.Protocols.SoapHeaderException: Could not find the iControl session for xxxxxxxx at System.Web.Services.Protocols.SoapHttpClientProtocol.ReadResponse(SoapClientMessage message, WebResponse response, Stream responseStream, Boolean asyncCall) at System.Web.Services.Protocols.SoapHttpClientProtocol.Invoke(String methodName, Object[] parameters) at iControl.LocalLBRule.query_rule(String[] rule_names) in d:\src\perforce\DevCentral\DC4\Labs\iControlAssembly\dotnet\iControl\Interfaces\LocalLB\LocalLBRule.cs:line 469

 

REQUEST: private LocalLBRuleRuleDefinition[] GetiRules(string[] rule_names) { try { LocalLBRuleRuleDefinition[] rules = m_interfaces.LocalLBRule.query_rule(rule_names); } }

 

What could be wrong here? Everything can be collected from the f5 except 1 irule information for 1 specific virtual server. Via soap there is no error. Also the call is in between of several other virtual server and irules and all of them are working except this specific one.

 

And the error looks more like a generic ones as I do not have any issues with the sessions during the whole run except here.

 

br, Patrick