I was shocked when Amazon pulled "The Chastity Belt" as part of their general clean out. It took me a while to realize that the issue was not the text but the product description, which used one or two keywords that triggered an automated tool.
So I fixed that, resubmitted a revised version, and it's back up!
Meanwhile, I've been revising "Getting Her to be a Vanilla Dominatrix". The 3rd(!) edition is leaner, better formatted, draws on two more years experience and research, and uses a simpler way of understanding your partner's modes. You should be able to update your copy by deleting it from your device and downloading it again.