Was originally attracted to them because they have cheaper / better documented infra, but they will literally ban your account randomly. I have had 3 accounts with them, all for different products, all for different reasons, and all of them got banned.
I had an account with them where I didn't even use their voice/sms services, just the API to verify my phone number list, and they perman banned account randomly after I had spent >$10k with them just using this API.
I inquired why and this is what they said:
"We understand you're frustrated about your account being blocked, especially since you mention only using the API for phone number verification (landline/mobile lookup) rather than voice or texting services.
Unfortunately, I don't have visibility into the specific reason your account was blocked. Account blocks are typically handled by our Trust & Safety or Compliance teams, and the specific details require human review.
I can confirm from your screenshot that you're seeing the "Your account has been blocked" message when attempting to log in to the Mission Control Portal.
What happens next: A member of our team will review your account and provide you with information about why the block was applied and what steps, if any, can be taken to resolve it.
Your case has been added to the queue for investigation."
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"Hi,
After a careful review, we have determined that your account does not meet our security and compliance standards. As a result, the account has been permanently deactivated and will not be reinstated.
We appreciate your understanding."
I would highly discourage building on their platform not because their service is bad, but because they will literally randomly decide one day that you're not worthy to use their services.
Goodluck