Say what work was done before the patch reappeared, approximately when, and how the area changed afterwards. Include products, repainting and known repairs. Current photographs should sit alongside older ones, clearly identified by date. Do not assume either a previous clean or a temporary clear surface proves the source was resolved.
Give a wider room view and explain the material. A general deep clean for other tasks is a separate request from assessing returning growth and moisture; another ordinary clean should not replace the enquiry.