mFTP is modeled based on your power curve. You need to have max efforts at key durations (think max power, v02max, threshold) for it to be accurate. If you haven’t done any max shorter efforts in the 90 days (or however you have wko5 setup) it thinks you have low anaerobic capacity (basically FRC). Underestimated FRC = overestimated FTP
If that’s the case for you, try some all out sprints and then a max 1-2 min effort and see how FRC and mFTP change.