diff --git a/FAQ-and-Troubleshooting.md b/FAQ-and-Troubleshooting.md
index 18a86de..0d27695 100644
--- a/FAQ-and-Troubleshooting.md
+++ b/FAQ-and-Troubleshooting.md
@@ -20,6 +20,17 @@ Thankfully there's a method for cleaning your CTRNAND (at least the parts requir
 7. If you have other NANDs to fix, repeat the process from step 3 to step 6
 7. Luma3DS should now be functioning normally, you can remove the `firmware.bin` from the `luma` folder and configure the **SysNAND is updated** option as needed
 
+## I have problems with GBA/DS/DSiWare games and I installed a patched AGB/TWL FIRM cia in the past
+
+There have been some reports of pre-patched AGB/TWL FIRM interfering with Luma3DS' built-in patching.
+Follow these steps to restore the unpatched Nintendo FIRMs:
+
+1. Get the NAND FIRMs package from [here](http://www56.zippyshare.com/v/TagKBxrI/file.html)
+2. From the NAND FIRMs package, copy `O3DS AGB.cia` and `O3DS TWL.cia` (if you have an Old3DS), or `N3DS AGB.cia` and `N3DS TWL.cia` (if you have a N3DS) to the SD card
+3. Open your favorite cia installer (the guide has been tested successfully with **FBI 2.1**). If you don't have one, it's outside the scope of this guide, look on GBATemp to check how to get your first cia installed
+4. Install the .cia files you copied in step 2
+5. Luma3DS should now be functioning normally
+
 ## I have a different issue
 
 - If coming from a previous version of Luma3DS and you have an issue, try to delete the `config.bin` in `luma` and try again.