to unlock your nuu f4l:
step 1: call the following number #6865625# ( or #nunlock# )
step 2: it will now ask you for a password your password is your IMEI
step 3: to find your IMEI press the back button and call the following number *#06#
step 4: write down the IMEI on a paper
step 5: call the #6865625# number again and enter the IMEI
(WARNING: this does not work on tagged nuu f4l phones)

zvirose it says password error

zvirose Mind if I simplify a bit:

NUU F4L Unlock Steps
Step 1: Find your IMEI by dialing *#06#
Step 2: Write down the IMEI
Step 3: Call #6865625# ( or #nunlock# ) and enter the IMEI for the password
(Tip: this does not work on tagged NUU f4l phones)