Q2686G Flash with incorect OS

I flash Q2686g modul (os r7.4) with xmodem to OS R7.44 for Q2687RD

after it modeule not registering in GSM and GPRS

afte it I flash with DWLWIN to R7.44 for Q2686g

But module bad work with GSM and not Up GPRS BEAREr. For connect to GPRS I use OpenAt application

PLZ How To Solve This Problem ?

I think that flashing new firmware resets all parameters to defaults - so any settings you changed before will have to be re-set.

In particular, have you set the correct frequency bands…?

After flashing I am not change frequency bands
I send command to module
+WMBS: 7,0

+WFM: “MONO900”,0,0
+WFM: “MONO1800”,0,0
+WFM: “MONO1900”,0,0
+WFM: “BI9001800”,0,0
+WFM: “BI9001900”,0,0
+WFM: “MONO850”,0,0
+WFM: “BI8501900”,0,0
+WFM: “EFR”,1,0
+WFM: “HR”,1,0
+WFM: “DATA144”,1,0
+WFM: “SIM1V8ONLY”,0,0
+WFM: “SIM1V8AND3V”,0,0
+WFM: “CPHS”,1,0
+WFM: “LOCA”,0,0
+WFM: “AMR”,1,0
+WFM: “NT_6K”,1,0

How to check frequency bands?
How to know frequency of GSM operator ?