SLA based in Service Category does not works!!

I have a question for you. At this time, We have installed SDP V 9.0, and we are trying to organize all the workflows and services. We have a Service Category named Applications, but when we try creating a SLA based in Service Category, the associated request don't has a SLA assigned. How can we fixing it? The goal is getting that created request through Service Catalog takes the SLA from Help Desk Customizer, but no take it from the SLA Service.

Thanks for your help.

Regards