Question I have tried everything AMD radeon

Sep 14, 2019

Laptop: Asus F555BP
AMD A9 7th generation
AMD Radeon R5 m420 2GB + AMD Radeon HD 8500M 1GB
8GB Onboard RAM DDR4

I just bought this Asus laptop, before buying it showed me dedicated Graphic memory of 3gb and I played Fortnite(Hate the game the owner was a kid) with medium graphic settings with an average of 36 FPS with power connected and it dropped on battery to 20 fps with windows 10 pro. hard drive was 1tb.
Today I replaced that 1tb hard drive with a SSD Drive and did a fresh windows 10 home single language install and now after updating windows and installing all drivers, my Dedicated graphic memory shrunk down to 1024mb from 3072mb.
I have pictures as well and one picture that kid sent me before buying the laptop is of how it use to be.

Please tell me how to fix this please.