Why did my iOS push notifications stop working for my Xamarin-based application?

If your iOS push notifications have stopped delivering for an application built with Xamarin, the underlying reason is that the framework is no longer supported and can no longer be kept in step with changes on the Apple side.

Microsoft ended support for Xamarin on May 1, 2024. The final supported targets were Android API 34 and the Xcode 15 SDKs (iOS/iPadOS 17). Pushwoosh no longer maintains or supports the Xamarin plugin, and Xamarin is no longer covered in the Pushwoosh SDK documentation.

Important: the end of support does not switch anything off by itself. Delivery usually breaks because of something the unmaintained plugin can no longer keep up with — for example an expired or revoked APNs auth key, a Sandbox/Production gateway mismatch, a bundle ID change, or an OS/toolchain update the old plugin was never built against. So before assuming the framework is at fault, check your iOS platform configuration in Pushwoosh (auth key, Key ID, Team ID, Bundle ID and gateway) and look at the actual APNs error returned for your sends.

Recommended path

Migrate your application to .NET MAUI, the supported successor to Xamarin. Pushwoosh provides a MAUI/.NET SDK:

• Pushwoosh .NET MAUI SDK integration

Applications that remain on unsupported frameworks may keep experiencing service disruptions, including push delivery failures, as platforms and dependencies evolve.