I hear you. I sometimes worry that my emotions show when I'm responding to a convo if someone has made a request that seems a bit different.
I've purchased from sellers of digital products a number of times. Some have very lengthy messages in their item descriptions, policy page & message to buyer about this being a digital product & "you will not be receiving anything in the mail" blah, blah, blah. I totally understand the rationale for doing that, even though it can be a lot for people to read.
Is there a reason you have to send the pattern within 24 hours? I'm wondering because I reserve the right not to ship orders if I have a question (like if something seems off in the address) until the buyer responds.