Toll Free Numbers (TFNs) work differently than regular inbound numbers. The company who is using the TFN has to pay for every inbound call. So, their TFN supplier can let them define which calling locations can call their TFN. For example, if you are a business or government agency that only has customers in, say, Iowa, then you can restrict inbound calls only to callers in Iowa. This is less common today than 20 years ago, what with internet e-commerce, but the restriction feature is still available. If your Anveo number appears to the TFN provider as if it was from a restricted area, then the call won't complete. Another example would be if Anveo is mangling your caller ID, and it looks like it's from another country, or if your caller ID or calling origin is blocked entirely. Now, if your Anveo number is legitimately within the TFN's allowed calling area, it really should be connected. If Anveo is playing games with call routing, they might be causing the problem. We do know that Anveo restricts calls to certain regular phone numbers, when the called number's phone company charges high termination rates, but that's a separate issue. Frankly, if this is a show-stopper to you, there are better alternative SIP ITSPs to which you can take your business...