RM520N-GL stuck in FTM (CFUN=5) after re-flash — restore QCN while keeping IMEI?

IoT Modules 5G Module
1 
Hi all,

My RM520N-GL is stuck in Factory Test Mode (CFUN=5) - the radio won't initialise.
AP/AT respond fine and the SIM reads, but:

- AT+CFUN?  -> +CFUN: 5
- AT+CFUN=1 -> +CME ERROR: 0
- AT+CSQ    -> 99,99 ; +CEREG: 0,0 ; +CGATT: 0
- AT+CEER   -> "No cause information available"
- AT+CPIN?  -> READY

Firmware RM520NGLAAR03A04M4G (also tried _A0.301), HW rev 20000, IMEI 869710030002905.

I've re-flashed the full image several times with QFirehose -f (never -e), but
CFUN=5 persists across firmware versions, reboots and power-cycles - looks like
the QCN/EFS2 calibration is gone.

Is there a supported way to restore the calibration / exit FTM while keeping the
original IMEI? @Silvia / Quectel staff - could you provide the QCN for this unit
or advise on recovery/RMA? Happy to share a full AT log. Thanks!
2

my email clembecerra@gmail.com

3

@Silvia I’ve made a Full EFS scan (359 NV files): protocol stack fully populated (wcdma/rrc 162 files, modem/uim 17, etc.), TCXO field_cal present — but /nv/item_files/rfnv/ holds a single 64 B item and /nv/item_store/rfnv/ is empty.

The per-unit RF calibration is wiped. Need the RF calibration / QCN for this unit; IMEI 869710030002905 preserved.