Default [Q] sprint galaxy s2 change esn and msl code us change also

Sorry my English is not good.I have sprint galaxy s2.its change ESN and now I can't connect to diag mode.Cuz. its msl code is some kind of word which is not on a square box than a question mark in box and than 13 and last is again square box 2 I have no idea how I used this msl code when phone asked me.