If you are unable to access Google Authenticator due to loss / change of device, uninstall Google Authenticator before performing the reset procedure and so on then you can take the following steps:

• Please login to your Indodax account.
• Please select the option 'Lost Google Authenticator?'
• Please enter your 'email' and 'phone number' to receive the OTP code.
• After that you will get a notification that the 'Reset Google Authenticator' was successful

For more information, please follow this guide: How to deactivate Google Authenticator on Indodax account?