Yeh, I think if they don’t reply is because they already have a good list of regulars, regulars are enough to support them for the day. One private told me she filters them out by the first visit, if good you then on the list if not then block. She also save the number under stuff like “fat guy” or “big dick” which is in the block list, yup they prefer regular or small.
Keep trying and maybe she will reply on her slow days.