diff --git a/LoopFollow/Helpers/AuthService.swift b/LoopFollow/Helpers/AuthService.swift
index c00b1db9b..d065054c8 100644
--- a/LoopFollow/Helpers/AuthService.swift
+++ b/LoopFollow/Helpers/AuthService.swift
@@ -7,7 +7,7 @@ import LocalAuthentication
 public enum AuthResult {
     case success
     case canceled
-    case unavailable
+    case unavailable(String)
     case failed
 }
 
@@ -29,7 +29,20 @@ public enum AuthService {
 
         var error: NSError?
         guard context.canEvaluatePolicy(.deviceOwnerAuthentication, error: &error) else {
-            completion(.unavailable)
+            var message = "Device authentication is not available. "
+
+            let biometryType = context.biometryType
+            if biometryType == .none {
+                message += "Please enable Face ID, Touch ID, or set up a device passcode in Settings."
+            } else if biometryType == .faceID {
+                message += "Face ID is not available. Please set up a device passcode in Settings."
+            } else if biometryType == .touchID {
+                message += "Touch ID is not available. Please set up a device passcode in Settings."
+            }
+
+            DispatchQueue.main.async {
+                completion(.unavailable(message))
+            }
             return
         }
 
diff --git a/LoopFollow/Remote/LoopAPNS/LoopAPNSBolusView.swift b/LoopFollow/Remote/LoopAPNS/LoopAPNSBolusView.swift
index d3ae79c9e..011fe0e10 100644
--- a/LoopFollow/Remote/LoopAPNS/LoopAPNSBolusView.swift
+++ b/LoopFollow/Remote/LoopAPNS/LoopAPNSBolusView.swift
@@ -326,20 +326,22 @@ struct LoopAPNSBolusView: View {
 
     private func authenticateAndSendInsulin() {
         AuthService.authenticate(reason: "Confirm your identity to send insulin.") { result in
-            switch result {
-            case .success:
-                sendInsulinConfirmed()
-            case .unavailable:
-                alertMessage = "Authentication not available"
-                alertType = .error
-                showAlert = true
-            case .failed:
-                alertMessage = "Authentication failed"
-                alertType = .error
-                showAlert = true
-            case .canceled:
-                // User canceled: no alert to avoid spammy UX
-                break
+            DispatchQueue.main.async {
+                switch result {
+                case .success:
+                    self.sendInsulinConfirmed()
+                case let .unavailable(message):
+                    self.alertMessage = message
+                    self.alertType = .error
+                    self.showAlert = true
+                case .failed:
+                    self.alertMessage = "Authentication failed"
+                    self.alertType = .error
+                    self.showAlert = true
+                case .canceled:
+                    // User canceled: no alert to avoid spammy UX
+                    break
+                }
             }
         }
     }
diff --git a/LoopFollow/Remote/TRC/BolusView.swift b/LoopFollow/Remote/TRC/BolusView.swift
index 0a70f86b9..30bfab213 100644
--- a/LoopFollow/Remote/TRC/BolusView.swift
+++ b/LoopFollow/Remote/TRC/BolusView.swift
@@ -113,8 +113,22 @@ struct BolusView: View {
                         message: Text("Are you sure you want to send \(InsulinFormatter.shared.string(bolusAmount)) U?"),
                         primaryButton: .default(Text("Confirm"), action: {
                             AuthService.authenticate(reason: "Confirm your identity to send bolus.") { result in
-                                if case .success = result {
-                                    sendBolus()
+                                DispatchQueue.main.async {
+                                    switch result {
+                                    case .success:
+                                        self.sendBolus()
+                                    case let .unavailable(message):
+                                        self.alertMessage = message
+                                        self.alertType = .validation
+                                        self.showAlert = true
+                                    case .failed:
+                                        self.alertMessage = "Authentication failed"
+                                        self.alertType = .validation
+                                        self.showAlert = true
+                                    case .canceled:
+                                        // User canceled, no alert
+                                        break
+                                    }
                                 }
                             }
                         }),
diff --git a/LoopFollow/Remote/TRC/MealView.swift b/LoopFollow/Remote/TRC/MealView.swift
index 517db1811..4c5e27df6 100644
--- a/LoopFollow/Remote/TRC/MealView.swift
+++ b/LoopFollow/Remote/TRC/MealView.swift
@@ -196,12 +196,26 @@ struct MealView: View {
                             DispatchQueue.main.asyncAfter(deadline: .now() + 0.1) {
                                 if bolusAmount > 0 {
                                     AuthService.authenticate(reason: "Confirm your identity to send bolus.") { result in
-                                        if case .success = result {
-                                            sendMealCommand()
+                                        DispatchQueue.main.async {
+                                            switch result {
+                                            case .success:
+                                                self.sendMealCommand()
+                                            case let .unavailable(message):
+                                                self.alertMessage = message
+                                                self.alertType = .validationError
+                                                self.showAlert = true
+                                            case .failed:
+                                                self.alertMessage = "Authentication failed"
+                                                self.alertType = .validationError
+                                                self.showAlert = true
+                                            case .canceled:
+                                                // User canceled, no alert
+                                                break
+                                            }
                                         }
                                     }
                                 } else {
-                                    sendMealCommand()
+                                    self.sendMealCommand()
                                 }
                             }
                         }),