One user experiencing login error before ever making it to the actual login screen through mobile app login

I have a user on an iPhone 8 that is experiencing an issue attempting to get to the login screen within my mobile app. They are the only person I’ve had that experiences this and I absolutely cannot figure out why. I have an iPhone myself and the login screen loads up just fine (as it does with my other close to 3k users).

The error is: invalid_request: Missing required parameter: response_type
Tracking ID: 2f784be9de6206191e23

Here’s a screenshot of the error screen they’re seeing:

Could this be something on their end causing this since I’ve not been able to reproduce on my side or from any other users?

Does ANYONE have any idea why only one user in my entire app would be seeing this error?