Excel Drag and Fill Handle not working as I would like

I am copying references from one workbook to another for organization. Both Workbooks are organized in tables. Earlier today I was able to filter table 2, by category in Column I, and paste the new Reference code in the correspoding Column M cell. For example I would filter by Column I in Book 2, Table 2, and the copy the reference from book 1, table 1. I would paste the reference into Cell M2. Because I had the filter applied I wanted to apply the reference to the end of the table in column M. So I was able to double click the drag and fill handle, and it would populate the rest of column M below in the table with identical references. Now, when I use the exact same method, double-clicking the drag and fill handle changes th reference entirely to previous reference no longer needed. The only options I have accessed were "Special" trying to clear formulas in other columns while leaving the text. Enable Fill handle and cell drag and drop, and Automatic Flash fill are both enabled. what is causing my issue, and how do I fix it?