@Nigel, you were right, but the prev/next still does not work.
I removed the parent group, in order to display the ‘current cell of the thing:converted to list’ of A directly on repeating group B, and it worked fine as you mentioned. However, the prev/next icon workflow still does not run.
I also tried to set the data source of repeating group B as ‘search for thing(no-constraints)’, but that did not make it work neither.
Additionally, I tried to use a simple group, instead of repeating group B. But when I tried to set its data source as’‘search for thing(no-constraints)’, it produces an issue. Since the data source of the group should be a list of the thing, and not a single one. Therefore, do not how else I can make it to display the next thing, which was the sole purpose of having the single-cell repeating group B.
Can you spot thru my explanations if I understood your msg wrong? Or do you have another idea to solve this prev/next action problem?