Flat looking breasts. How can this be improved? (Photo)

The breasts do look normal for this stage of healing with a medium profile implant. The boxiness is expected to improve with time as the tissues settle into position. With respect to the flatness, an implant with higher projection may be what you are looking for. A push up bra may help if you do not want a different implant.
I recommend you allow the tissues to continue to heal and don't consider further surgery for at least another 6 months.

Dear sarasara1234,
I understand your concern. However, without a proper assessment, it would be difficult to determine what went wrong. It is best that you visit your plastic surgeon for further assessment or ask for a second opinion. Only after a thorough examination, you can get proper recommendations and advice.
Daniel Barrett, MDCertified, American Board of Plastic SurgeryMember, American Society of Plastic SurgeryMember, American Society of Aesthetic Plastic Surgery

There are several possible reasons why your breasts may appear flat and boxy after a breast lift and implants:

Swelling: It is common for swelling to persist for several months after surgery, which can make your breasts look flat or boxy.
Implant position: If the implants are too high or too low, or if they are not centered properly, this can lead to an unnatural or boxy appearance.
Implant size or profile: The size and profile of the implants can also affect the shape of your breasts. If the implants are too large for your body, this can make your breasts look overly full and round, or even flat.
Breast tissue: The amount and quality of your breast tissue can also impact the final shape and appearance of your breasts.
It is best to discuss your concerns with your surgeon, who can evaluate your breasts and determine if there is a problem that requires revision surgery. Depending on the cause of the problem, your surgeon may recommend different options, such as adjusting the implant position, changing the implant size or profile, or performing a revision breast lift.

Best of luck !

Just based on your one photo, you might consider going larger with a higher profile implant that is placed behind the muscle.

Ii would love to see before photos and present photos with both the front and side views.
It could be from a variety of issues. Your single photo now looks acceptable, but you do lack upper pole fullness which is common after the implants settle into the pockets.

Your implants are under the muscle.
It appears that the left implant has partially herniated out of the pocket
I would not rush to do anything right now .In the future if you decide to change the implants ,you may want to consider placement above the muscle