AC779s unlocked but not?

[LoyalServant]

long story short, device is detected and it said it unlocked successfully after getting the 10 credits.
No SIM was installed.
But when I put another sim in it, it's locked again.
Says:
SIM Lock Status: (PH-NET PIN)

Tried two other known good sim cards but the instant they are inserted it becomes locked again.

In the device's web ui it says:

• Invalid SIM
  
  The inserted SIM cannot be used with this device.
• Mobile Broadband Disconnected
  
  

Any ideas?

[Valdemaras]

Please repeat unlock with same account as it does not ask for new credits and make sure device is not reseted after doing the unlock.