There is no official account verification workflow, but we use Twilio to verify phone numbers (that end up verifying an account) using standard Bubble capabilities.
First, we verify email address. Then, upon logging in following that first phase of verification we show a popup that prompts a person to enter a phone number for further verification. We ask if they want SMS or voice/call verification. In a workflow we create a random new 6 digit number variable in a field on the user called phone_verification_code. If SMS is selected, we send a text with Twilio to confirm (they are sent the code, and must enter it next — it must match the code assigned to that user profile. We allow 3 attempts per phone number per 24hr period to prevent abuse. If voice/call is selected, we use Zapier to send a text-to-voice message to that person. Same as SMS< we limit this to 3 attempts per 24hrs.
After confirming the account with SMS we toggle a boolean variable “sms_verified” to yes and save the number and do a few more things to allow notifications for that device.
This has worked great and covers almost every scenario we’ve come across.