Local code for engineer mode doesn't work on Realme devices

[rafnov]

Checklist

• I can reproduce the bug with the latest version given here.
• I made sure that there are no existing issues - open or closed - to which I could contribute my information.
• I made sure that there are no existing discussions - open or closed - to which I could contribute my information.
• I have read the FAQs inside the app (Menu -> About -> FAQs) and my problem isn't listed.
• I have taken the time to fill in all the required details. I understand that the bug report will be dismissed otherwise.
• This issue contains only one bug.
• I have read and understood the contribution guidelines.

Affected app version

1.5.1

Affected Android/Custom ROM version

Android 13 stock

Affected device model

Realme GT Neo2

How did you install the app?

F-Droid / IzzyOnDroid

Steps to reproduce the bug

Try to enter engineer mode on Realme device via *#899# code

Expected behavior

Entering engineer mode

Actual behavior

Message about wrong USSD / MMI code

Screenshots/Screen recordings

I have Realme device. It's from BBK company, similar system to Oppo, Vivo, OnePlus. On Fossify Phone one important feature doesn't work: entering engineer mode via code: *#899#.
Why it doesn't work and it's treated like USSD code? I need to switch to Google ugly phone to use it.

Additional information

I have tried that on Realme 7 pro with Android 12, stock
Fossify Phone sends code *#899# as an ordinary USSD and the message appears: problem with connection or wrong MMI code.