Thank you for your kind comments, Katie! Very cool you're doing human design readings.
You have to stay in a high vibration - yes - but you can still connect with negative entities in high vibration because they are also only energy and not physical matter. Low vibration make it worse. So it's important to make sure other aspects of your life are in good working order, so to speak.
For example, if you're dealing with your own emotional wounds and not the greatest self-esteem or having self-doubt, this can affect what you pick up, and/or how you interpret it.
And if you were stuck in an abusive relationship and the destructive beliefs and cycles of that, it can affect what comes in when you "tune in." This kind of situation is all too common - sadly - because there are a lot of people who are being abused or who are in toxic relationships and wouldn't even know it or call them that.
So it can be a little messy to do readings if we don't have a relatively solid inner world. Also good to have some sort of practices to keep yourself protected on a daily basis and especially, immediately before doing readings.
Have fun!!