Hi, Could you confirm if 48 hours have passed since the purchase? Sometimes it can take up to 48 hours for the upgrade to reflect on your account. If it’s already been more than 48 hours and the storage still hasn’t updated, you’ll need to contact Microsoft billing support so they can check your account.
To get help, open the "Get Help" app on your computer (just search for it in the Start menu). or go to https://support.microsoft.com/contactus, Type "Billing" and press Enter. On the next screen, click "Contact support" at the bottom of the page, then choose "Microsoft 365" > "Manage my subscription". You’ll then see the option to chat with a Microsoft support agent who has access to your account to help review the issue.