ITMS-90896 Error when uploading binary with Transporter

Hi

I have an app with an Intents extension and a Widget extension that is failing to upload to App Store connect. I am receiving the following error and I have no idea how to fix it

ERROR ITMS-90896: "Invalid Mach-O header. The __swift5_entry section is missing for extension bundle Payload/[AppName].app/PlugIns/WidgetsExtension.appex, which prevents the extension from running. You can run the otool command against your binary to ensure there is a __swift5_entry section."

This worked fine a couple of months ago on last submission.

Thanks Alan