UPDATE: I redesigned my entire app and resubmitted it: it got rejected again for not having good resolution on iPad. My app literally doesn't make sense to use on an iPad... What should I do? I tried incorporating autolayout but that is honestly the hardest and most annoying tool Apple has created.

Change the settings to not support ipad and then re submit
They won’t test on ipad if you don’t allow support

True ^

@lewdogg I have removed every reference to iPad from my entire app, they still rejected it...

Is it a universal app?
What do your project settings look like?

@lewdogg it's not a universal app. I selected "iPhone" under devices in my Deployment Info. Also in Build Settings the Target Device is set 1 which is iPhone only.

Okay, but it used to... correct?
Sounds like you need to do an appeal to the reviewers.
They probably need to refresh their info on the app now that you have removed support for ipad.
I have had to do this before... either in the “notes for tester” field or an actual appeal thru their appeal system.

@lewdogg thanks for helping. I did put it into the notes, but they said that all iPhone apps have to run at iPhone resolution on an iPad.

Oh okay, that makes sense.
Make sure you have all your assets then at the required resolutions ... @2x @3x etc