We know the ramp test formula, 75% x last avg min power… the 75% is not set in stone, everyone isn’t the same, believe the 75% was ‘accurate’ for majority, though some do need to take it down to 70 and others up to 80. We are all different…
You may find altering the formula gives yourself a more accurate FTP. If I was finding it over estimating, I would change the formula to 70% x last avg min power and see how that works out for you Then take that formula forward for all future tests.
There are some threads on over testing you may find interesting.