Darragh here from Airship Support. Thanks for writing into our forums.
So, it appears as though our system is not recognising your certificate as development. I know that this is a bit of an inconvenience, but would you mind creating a new Development Certificate and attempting to upload this, please?
Apple Certificates are only valid for one year so yours may have expired, which would remove it from our system - this is not the guaranteed answer as to why it is no longer in your app, but the most likely the cause.
Please let us know if the new Development Certificate that you create doesn't work.
Technical Support Engineer
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