[Realme 6 Pro Questions & Answers] said1219:
I have the exact same issue. This problem generally applies to all Realme devices upgraded to Realme UI 2.0. The root cause is the disabling of com.coloros.weather.service package, usually done during debloating through adb. Further analysis I have done is explained on my thread.

Quick fixes you have now:

If you have adb enabled and ticked "Always allow from this computer" on the prompt below when your phone is still working, you can connect your phone in the blinking state and issue the following command: adb shell cmd pm enable com.coloros.weather.service. Then, reboot your phone. It will work normally on Realme UI 2.0.

[DATA LOSS] Download this ozip and put it on an SD card. A used SD card works fine as long as it isn't encrypted and has enough free space.

Make sure the file name matches your device model.

Enter realme UI Recovery (on Realme 7, you press VolumeDown + Power, which might differ for each device) and choose 'Install from Storage'. Enter your device password, select 'SD Card', and pick the ozip you have downloaded. The phone will wipe itself, and you end up with a working phone on Realme UI 1.0.

[DATA LOSS] If your phone is still on warranty period, go to any Realme Service Centre, and use the following statement; the service centre will either replace your phone free of charge or if they don't have any replacements in stock, put you on a waitlist and calls you back once the replacement device is available.

Other possible, longer-term solutions are:

Wait for Realme to realize this problem and issue an OTA update. The fix is easy on their side; just add a simple one line on the after-flash script of the next OTA/ozip to enable the weather services package:

pm enable com.coloros.weather.service

The command pm enable would do nothing if a package is already enabled. However, Realme might not realise this problem. Even if they recognise it, Realme might think it is not their own problem (debloating = user's fault?). If they release this fix, we can just boot into recovery and install it. Realme has support for OTA updates on their recovery. Just enter the device password and then the WiFi password.

I have tried exploring the Realme forums, albeit not directly filing a bug report. I found many, many users experiencing a similar issue as ourselves. Most of it was responded to by Realme representatives in this fashion: "enter recovery mode by pressing this and this, and then choose to wipe data. This will reset your phone to its working state." This is not acceptable for me since a functioning phone is lower on my priority than keeping my data (albeit in limbo).

Suppose your device has MediaTek SoC, and you have not set up any password/PIN/pattern on your device. In that case, you could possibly extract the userdata partition, exploiting the Boot ROM (BROM) exploit by Dinolek and k4y0z with the SP Flash Tool. You first need to find a specific scatter file for your device; however, if none is available, you could generate one from a preloader dump using a tool named Wwr MTK.

If you have set up a password, then this would be infeasible, apparently, since not only the device password is needed to decrypt it, but also some salt stored on the SoC itself; hence this thread highly suggests swapping SoC and eMMC to another working exact same phone (cannibalize another phone).

However, even after you swapped the SoC to a new phone and write your userdata partition on it, you faced a new dilemma:

previously on the old phone, you have a non-working software config, but the decryption key to the userdata is the same as the decryption key to the other partitions

now on the new phone, you have a working software config. The decryption key is available on SoC, but the other partitions are unreadable to the bootloader. They are either unencrypted or encrypted with a different key.

I have not been able to solve the above dilemma.

Hence, my current objective is to nag Realme and invite others to also nag them to implement that simple one line on their OTA update.