I hope this is a quick question and that I am asking it correctly

This evening I was going into KSBA and was told to expect the approach VOR 25 @ KWANG , well KWANG came and gone and nothing.

So I queried the approach controller and not sure if it was radio issues but still no clearance.
So my question is how long after the the fix or location I was told to expect the approach clearance should I query the controller or just hang out until they remember me?

Thanks
BTW - I want to say even when things are busy, people are confused the controllers keep a very level head and seem to maintain great composure. Get up the great work/service.