CoreBook x i5-8259u ssd suggestions

Hello everyone, I own a CoreBook X i5-8259U (512 GB SSD) and lately my laptop has become really slow. CrystalDiskMark shows my current SSD is underperforming badly, so I’m planning to replace it. Could anybody with the same model (who has successfully upgraded their SSD) recommend SSDs that have worked well for you?

Hello.

The computer must be about 5 years old or more, that’s why it’s slow.

How do you need to replace it. Open the hard drive compartment and you can see the drive and its specifications.

Helo, I am asking for SSD brand recommendations