How to delete an google account can be different to the version of Android.
This example is done for our IS655.2 with Android 9.
For this it is necessary to have access to the device.
- Swipe to the Menu and choose Settings
- Press Accounts
- take your Google Account
- Press button Remove Account
- Confirm the removement of the account
The Google Account is successfully deleted.
More information about how to delete a Google Account is to find directly at Google Android page