Are you actually working with these spirits in developing your senses, or are you continuing to expect them to do everything for you?
What you should be doing is:
1: Open the seal of Sastan with the intention of getting his help in developing your senses
2: Once the seal is open, turn your gaze to a scrying mirror, bowl of water, or other dark surface, and simply let your mind be open to perceiving any images that come up.
3: Do this daily for about a week or two.
Choose 5 spirits to contact, and write down 5 questions to ask each of them.
1: Open the seal of the first spirit, and once it is open, ask your questions. Pause after you ask each question and write down whatever you hear in your mind, regardless of what it is.
Don’t second guess yourself. Just write down whatever pops into your head after you ask the questions, and then thank the spirit. Put the seal and list of answers away for a day or two, then take the answers out and study them. Try to find any differences in grammar or syntax that don’t match your usual inner voice.
Repeat for the next 4 spirits. You should be able to spot anything that stands out from the pattern of your usual way of inner speaking. That will be the voice of the spirit.
These two exercises are taken directly from EA’s evocation course.
You should also be practicing trancework daily.