How can I fix the flatness on top of my cheek? (photos)

It looks like the dents/depressions on your cheeks could be helped with the use of filler.  There are many that will give you an instant result lasting up to a year.   

The eye area needs significant combinations to get improvement. Lasers like erbium, co2, halo, profractional/contour, or Fraxel can all be used to build collagen long term. Plasma pen is a newer less invasive option but will take many treatments and require proper skincare. Plasma Pen is focused electrical plasma energy to tighten skin, producing small columns of energy just above the skin, allowing the skin to tighten to help improve wrinkles. This area will have 3-5 days of small “dots” that will then scab and peel, then the skin will tighter and brighter after. Numerous treatments are needed over lasers where only one or two give a bigger result, but more downtime. After plasma pen you NEED peels 2 weeks like later Cosmelan, enlighten or aerify, see emeragecosmetics (link). At home derma rolling should be started weekly even after plasma pen or lasers to further increase collagen, see emeragecosmetics AERIFY x anteagemd stem cell ampules. To properly heal you need light Stim red LED, EmerageSkin refit face, refit eye; AnteageMD serum, silagen silicone gel, jan Marini bioshield, EmerageSkin enzymatic polish, and EmerageSkin hyla b and AOX, and Sente dermal repair. Otherwise there is EXTREME risk of pigmentation issues and “dots” in the treatment area. at home peels like cosmelan, enlighten and aerify along with dermarolling (AERIFY emerageskin roller with Anteage MD ampules) should be started now regardless for antiaging, sun damage, and wrinkle prevention. There are many things you can do to treat under eye hollows and dark circles. A surgical option to remove skin and/or fat will such as eyelid blepharoplasty with or without fat pad repositioning (if doing lower eyelid surgery) will be the best long term. There are many things you can do to treat under eye hollows and dark circles without surgery. Non invasive less downtime options such as fillers, lasers, microneedling/PRP, cosmelan peels, and microneedling RF like Fractora, PiXel8 or morpheus can all help give some improvement. Accutite can often be used or stronger lasers like erbium or co2 spot treatment can tighten the skin and give very quick improvement in wrinkles and texture. I suggest you get a formal consultation to see what is best for you and your goals. Best, Dr. Emer.

It is possible that you may need a touch up treatment using HA fillers as you are a year out from treatment.  Voluma and Lyft are both excellent HA fillers that provide beautiful, natural and lasting volume to the mid face and cheek.  Evaluation of your tear troughs should be reviewed with your provider.  It is possible that filling the mid face may correct some of your tear trough concerns.  If not, treatments such as laser, radiofrequency, botox and filler can be used to correct the area.