Here is my implementation on capturing adpu, where it initailly seems to work. But then all of a sudden deselected is triggered: do { for try await event in session!.eventStream { switch event { case .sessionStarted: print("Session started ... !") session!.alertMessage = String(localized: "Communicating with device.") case .readerDetected: print("Reader detected") try await session!.startEmulation() case .readerDeselected: print("Reader deselected") await session!.stopEmulation(status: .success) case .received(let apdu): do { print("Received APDU \(apdu)") let responseAPDU = ProcessAPDU(apdu.payload) try await apdu.respond(response: responseAPDU) print("Response APDU successfully sent") } catch { print("Error responding to APDU: \(error)") } case .sessionInvalidated(let reason): print("Session invalidated: \(reason)") session!.alertMessage = String(localized: "Ending communication with device.") session = nil @unknown default: print("Unknown event") } } } catch { print("Error during event stream: \(error)") } Session started ... ! Reader detected Received APDU {Responded=false, Payload=16 bytes} .. more back and forth.. Response APDU successfully sent Reader deselected default 11:21:42.631634+0100 nfcd -[_NFCardSession sendAPDU:startReadOnCompletion:completion:]:512 Runner default 11:21:42.631675+0100 nfcd -[_NFCardSession sendAPDU:startReadOnCompletion:completion:]:513 {length = 2, bytes = 0x6a81} default 11:21:42.632040+0100 nfcd -[_NFCardSession sendAPDU:startReadOnCompletion:completion:]:544 isSent: 1 default 11:21:42.642265+0100 nfcd -[_NFCardSession sendAPDU:startReadOnCompletion:completion:]:512 Runner default 11:21:42.642335+0100 nfcd -[_NFCardSession sendAPDU:startReadOnCompletion:completion:]:513 {length = 22, bytes = 0xXXXXX} default 11:21:42.642716+0100 nfcd -[_NFCardSession sendAPDU:startReadOnCompletion:completion:]:544 isSent: 1 default 11:21:42.652183+0100 nfcd -[_NFCardSession sendAPDU:startReadOnCompletion:completion:]:512 Runner default 11:21:42.652242+0100 nfcd -[_NFCardSession sendAPDU:startReadOnCompletion:completion:]:513 {length = 18, bytes = 0xXXXXX} default 11:21:42.653002+0100 nfcd -[_NFCardSession sendAPDU:startReadOnCompletion:completion:]:544 isSent: 1 default 11:21:42.670001+0100 nfcd -[_NFCardSession sendAPDU:startReadOnCompletion:completion:]:512 Runner default 11:21:42.670075+0100 nfcd -[_NFCardSession sendAPDU:startReadOnCompletion:completion:]:513 {length = 18, bytes = 0xXXXXX} default 11:21:42.670627+0100 nfcd -[_NFCardSession sendAPDU:startReadOnCompletion:completion:]:544 isSent: 1 error 11:21:42.675772+0100 nfcd phOsalNfc_LogStr:65 Rf LinkLoss in DiscMode.. error 11:21:42.676106+0100 nfcd -[_NFCardSession validateReceivedAPDU:]:236 Invalid ISO7816 APDU detected, (null) default 11:21:42.676153+0100 nfcd -[_NFCardSession sendAPDU:startReadOnCompletion:completion:]:512 Runner default 11:21:42.676196+0100 nfcd -[_NFCardSession sendAPDU:startReadOnCompletion:completion:]:513 {length = 2, bytes = 0x6a81} error 11:21:42.676505+0100 nfcd phOsalNfc_LogStr:65 State machine status is NFCSTATUS_REJECTED error 11:21:42.677401+0100 nfcd NFDriverRemoteDevSend:6531 phLibNfc_RemoteDev_Send failed 0x0038