iOS "Unknown Error = -2,147,409,850" while trying to generate Certificate Signing Request (CSR)

[bcspragu]

I'm packaging a PWA as an iOS app using PWABuilder, and I'm hitting a wall on step 3, where I'm supposed to use Keychain Access/Certificate Assistant to generate a CSR, but it keeps failing with the error mentioned in the title. If it makes a difference, I don't have any physical Mac hardware, so I'm using an AWS Mac instance and have logged into that with my Apple Developer account.

I could only find one other mention of this specific error code on the entire internet, which definitely, definitely does not bode well for me. Any help is much appreciated!

I've tried a few workarounds I saw for other, similar Keychain Access errors on the internet, e.g. selecting "Let me specify key pair information", but the error remains the same, screenshot below:

[jgw96]

@khmyznikov any ideas on this one?

[bcspragu]

For what it's worth, I fixed this by just using someone's physical MacBook to generate the keys, not sure if the issue is specific to AWS Macs or not.