In order to upgrade your VPS components (Such as RAMs, Storage .. etc), do the following:
1- Login to your account in our website and click on your VPS to check its details
2- In the left side menu, Click on "Upgrade/Downgrade Options"
3- You are able now to upgrade for additional storage, RAMs .. etc and click "Click to Continue"
4- Changes will take effect immediately once you complete the purchase.
5- Restart your VPS