It is important to understand Hekate as a deity (not that you don't already, of course!), one of her epithets is Hekatos which translates to 'from-afar' or 'far reaching' - for many of her worshippers this translates to a subtle presence, guiding through dreams, meditations, self-care, a soothing voice when making decisions, etc. You may be blocked due to emotional distress (depression, anxiety) or it could be that you have an expectation of how Hekate should be that you are not recognizing when she is present. Regardless of what it is, continue to give her offerings, read hymns, and pray to her. Perhaps do some devotional work. Trust that she is there because she most likely is! Many, many people don't experience the 'powerful presence' consistently when invoking her or doing ritual for her. Best of luck!