You can only modify your home currency if the multi-currency feature in QuickBooks Online Account (QBOA) hasn't been activated, Jenelyne.

First, you'll want to check whether the multi-currency feature is active in your account. If it's already enabled and applied to your transactions, QBO won't allow you to change your home currency. If you really want to make changes to your home currency, you'll have purge everything from scratch and start over.

You can check the picture below for reference:

If not, you'll have the option to update your home currency by following the steps outlined below:

1. Go to the Gear icon and select Company Settings.
2. Navigate to Advanced,
3. In the Currency section, click Edit.
4. Select the PHP - Philippine Peso from the Home Currency dropdown.
5. Once done, click Save to apply the changes.

Please note that if you've already entered transactions using US Dollars (USD), changing the currency symbol will not automatically change the numerical amounts. To correctly apply taxes based on your new home currency, you'll have to manually adjust those existing figures.

Feel free to reply to this post if you need further assistance.