Hi @mdickens When Vapi rejects SIP calls, it’s usually due to authentication issues (credentials/IP whitelisting), codec mismatches, or incorrect SIP INVITE formatting. Are you getting a specific error code like 403 or 401? That would help narrow it down. Check out Vapi’s SIP docs here: https://docs.vapi.ai/telephony/inbound/sip - they cover the setup and troubleshooting pretty thoroughly. If you’re still stuck after going through that, I’m available to help dig into it. Happy to jump on a call if needed