Validating Mobile Phone Numbers in Clay: Tips and Challenges

Hi Clay Team, How do we validate mobile phone number generated in Clay are all valid. Like email you have Zero Bounce as validation provider, but for phone number there is none. I have use multiple data provider like Forager, Lead Magic and it seem that the mobile phone number we are getting are toll free numbers from companies instead of our ICP, when we cold call we are routed to an IVR or Gatekeeper.