You could be seeing a regional ad. in addition to that possibility, sometimes the placement and service of ads change and the block rules have to be fine tuned.I am new to ad blocking on iOS but have just bought Purify, mainly due to the developer's willingness to participate in this thread. However, why am I still seeing the large Amazon ad just after the last post on a page on this site?
Chris will probably respond to your post. Just the same, it is best to report the site through the app.