Help/Support About UDID, UUID and IDFA’s

[blacksmith40 65 iPhone 8 Plus 12.0]

Hello everyone, I am using a paid app’s (don’t bother what it is) trial version. After my trial is ended, its system recognizes my phone and I can’t start a new trial with a new account. I dont know how it does that but I have couple of guesses. 

1- It remembers my UDID or UUID. (Not sure whether they are allowed to do this)

2- It might remember my advertising Vendor (IDFV)

Extra Information that might be useful

1- It doesn’t check my advertising identifier (IDFA), because when i reset my IDFA, system still recognizes my phone.

2- When I reinstall the app it still recognizes my device.

3- When I reset my phone to factory settings ( erase all contents and settings) , It doesn’t recognize anymore, so I can use its trial again and again by doing this but there should be an easier way to do this and that is why I am here. 😕

4- After resetting my phone to factory settings, it works ( as I mentioned earlier) but when I load my previous backup, It starts back recognizing my device  

 

I hope there is someone who can help me. I need to change my device’s information without resetting my phone to factory settings. There should be an easier way and I believe you can help me 🙏 . 

 

Edit: My device is Jailbroken so you can suggest me tweak apps

 

[X204 38.5k iPhone 5s 20.0]

I believe using Apps Manager and  wipe app data will do the same thing no need to rest your phone , (don’t backup your app data if you did that the app will recognize you when you load your backup)  also try to use cacheClearer.