Inbound 486 USER_BUSY / dial_busy — per-CALLER, legitimate calls dropped Agent ID: agent_8fbc66e7be3e0dde727f73a42b Retell DID (inbound): +19499195585 (Telnyx) disconnection_reason: dial_busy (no entry in Call History — rejected at SBC) Same trunk/agent/region. Result depends ONLY on the calling number: - Verizon ×2 callers → both connect - T-Mobile ×2 callers → one connects, one gets 486 - Caller +13237681438 → 486 (trace below) Call-ID: bce8fa42-48af-4f77-af64-f62b524947b8 Time: 2026-06-17 23:05:35 UTC SIP from your SBC 18.98.16.120: 100 Trying → 180 Ringing → 486 Rejected (~380ms) This looks like per-caller spam/reputation rejection at your SBC. Please disable inbound spam-screening / whitelist DID +19499195585.