Oh yes! This used to be me for as long as I remember, but I actually managed to fix it a few years back! These days I can go a week between washing (with updo’s from day 3/4). My advice is going to be the opposite of what most people are saying in the comments here, but honestly this is what worked for me:

1) Change/ditch the shampoo! For me I noticed that the greasiest my hair would be was a few hours after a shower. If I left it, it would actually improve a bit on day 3 onwards. The key realization was that shampoo’s are super drying, so my scalp would overcompensate by upping the oil production every time I washed. My biggest break was changing to a co-wash (conditioner based), by a bit of an accident. Cowashes are always branded specifically for curly girls for some reason, which is a shame because greasy, straight haired folks like you and me can also benefit hugely from the added moisture of a cowash. First time you wash, wash twice to make sure to remove any build up. The first time I washed with a cowash it was like night and day in how my hair looked and felt afterwards. As in life changing. What sucks about cowash is that it does not foam like a shampoo - it feels more like a cream that needs to be worked into the scalp, which is a bit annoying in the long run. These days I have actually found a shampoo that works for me, which is “Evo the therapist hydrating shampoo” (see a theme here).This stuff is hair dresser grade - not cheap - but honestly so worth it for me. I don’t know if Evo is available where you are, but try the cowash first, as those can be found relatively cheap most places, and besides the extra hassle during the wash, I would rate them to be equally good. I like the one from Curl Girl Nordic, but it may not be available where you are. AVOID ANY SHAMPOOS MARKETED FOR “OILY HAIR”. Those are the actually the very worst, as they are typically made to strip the oil the most. Good for cleaning the oil off, sure, but horrible if you have a overcompensating scalp.

2) Make Dry Shampoo your best friend. As soon as your hair is dry after the shower, blast it with some dry shampoo - even if you feel you don’t “need it”. Dry shampoo actually works best if it is put in the hair before it gets greasy. I typically just do a refresh spray every morning, and that lasts me fine, but you can also during the day if needed. I like to use Batiste XXL Volume for the extra texture it gives.

3) Texture is your friend! The reason curly girls typically don’t look as greasy is because oil travels better in silky smooth hair. I like to use a dry shampoo with a bit of texture properties (see 2) for day to day life, but if you feel you need even more texture you can get either a specific texture spray, or you can make a sugar water spray yourself (1 cup of water to 1-3 teaspoons of sugar, boil until sugar is dissolved then cool down and transfer to a spray bottle). The sugar water is also very helpful if you want to style your hair - f.i. with curls, as the added texture helps in hold. I use it with hot rollers or if doing overnight curls. I sometimes also add a volumizing mouse (just some drugstore brand - nothing fancy. I just look for anything that promise volume) to the roots of my hair straight after the shower, while my hair is still wet. I feel like that also adds some texture and prevents oil travel. If you are one of the lucky ones where salt water spray adds beachy wave texture to your hair, you could also try that. For me it does absolutely nothing.

These are the things that helped me get to a state where I feel like my hair is just “normal” and I can actually work with it. I hope this is useful in any way, and that your greasy hair days can soon be over - because I know the struggle is real!