When you change your currency or timezone, your existing ad account will be deactivated and all ads will stop running. You will not be able to reactivate this ad account. A new ad account will be created automatically. Use the new ad account to run your ads. This ensures that your ad performance, billable events, and bills sent to and paid by you are recorded in your ad account's new timezone and currency.

You also need to recreate any Custom Audiences and Facebook pixels in the new ad account.

* Nguồn: Facebook