1. Its all power to weight ratio
2. make small long term changes to diet, cut all alcohol, no fry, increase veg, balance protein and carb
3. Your doing the same mileage/effort each week. This isn’t any training its junk miles.
4. Mix up training, include hill work, intervals, speed and vary distance and effort to increase power, turbo in winter
<I commute to work by bike, cycling between 36-56 miles a day monday to friday, and then often a 30 mile ride on either saturday or sunday>
Its just mileage little training, no structure no rest. You get fitter when your body recovers. Body is simply bored its adapted to your life style.