Heya glamour eyes, further up there is a note advising how non pro prods can make your hair dirtier faster too. It hasn't gone into depth though. However you need to break the cycle.
Every stand of hair has a sabatious (can't work out how it's spelt) which produces sebum 'grease' these are essential to your hair and scalp. However too much will make you appear greasy, when you wash, brush, touch, move your hair, the wind moves it etc, you are telling them to work, they are already in overdrive as they are replacing the oils you keep removing but on top of this you are massaging, brushing, drying, styling everyday which again is telling them to work. So they are in super overdrive.
Trick is, get a good pro shampoo specifically designed for your hair and hair needs... Speak to your stylist or describe your hair and we'll all suggest some to minimise the search for you... When you apply conditioner do you just dollop it on your head or keep to mid lengths and ends (pony tail section)? Do you do 2 washes still?
Let it go that extra day and for a short period of time, learn to like dry shampoo, most of the time it's in your hair how your hair looks greasy and most people would think its fine. But use the dry shampoo on day 2 day 3 wash again, if lathers dont bother with a 2nd its clean and small amount of conditioner on the ends again, it will take a couple months but eventually it will be fine for the 2 days, this is when you then train it to go 3.. I wash mine when it needs it, usually every 3-4 days, occasionally 2 days if I've been messing with it more.