iOS APNS through Amazon SNS and Unity - Cannot create a development iOS certificate

I'm trying to set up push notifications through Amazon SNS in Unity.

I have the Android side of things working perfectly but we're having issues with iOS. I am able to get the device to register to a Apple Production SNS application and subscribe to a topic but as soon as I attempt to send a notification the endpoints "Enabled" status becomes "False".

I read that this could be due to the certificate being set as Production although we followed the instructions on creating a Development certificate, when I try uploading the .p12 file to create an Apple Development platform in SNS it always gives an error saying:

"You provided a certificate of type iOS Production"

We have tried multiple times to download the development certificate and tried rebuilding the app with a new bundle ID and new app on the Apple development site without touching the production button but it always ends up being a production certificate after exporting the .p12 from KeyChain...

Also, every .p12 we have created had the exact private key and certificate as the last.

What could be going wrong?