There are actually two IDs: the HTML ID (which can be edited) and the Bricks element ID. In principle, these are initially the same.
However, after renaming the HTML ID, it still refers internally to the Bricks element ID. In other words, the Bricks element ID is not renamed, as this would create a huge mess.
Based on the form name, however, you should be able to recognize the form within the submissions.
This issue is not the same, as I assume that the section containing the form was saved as a template, or the page was duplicated with some plugin, and the IDs were not updated as a result. We already have several reports on this and are working on a solution. The problem is described here using popup templates: WIP: Links & Inputs broken in popup, CSS overridden out of nowhere - #4 by mr.matt.eastwood