Service Request Number is not coming in auto acknowledgement mail

Hello Team ,

I have scenario ,where system create service request from the incoming email based on the content and immediately it has to send the auto acknowledgement mail with the service request number that is generated.

I have created the rule policy as below :

If Email content contains Query

then create Service Request   ZQRY

Send auto acknowledgement

Mail form - Z_AUTOACK

Outbound email address - xyz @xyz.com

Create Interaction Record - NO

Creater Service Order - NO

Create Service Request - NO

System creating service request of type ZQRY correctly and also system sending the auto acknowledgement but service request number not coming in the acknowledgement email.

I created the mail form (Z_AUTOACK) under create mail forms in the UI in IC_Manager role and inserted the attribute "service request number"

whether iam missing some thing as why system not updating or inserting the service request number in the auto acknowledgement email.

Regards

Kumar