What code does the phone ask for? 

sim pin code or something else?

Pin

Samsung Galaxy A12

How many digits you must enter? 

You can find the simpincode on your MijnSimyo page or in the app. 

Go to instellingen (settings), Simkaart (simcard) and by Pincode click on ten eye to see the code. If that's not the code to unluck your phone it must be be the code to unlock your screen. That is an code you made yourself. 

Hi Kaapstad, 

Welcome to our forum!

If your cell phone is asking for a SIM PIN and the provided PIN-code doesn't work, then maybe you should try unlocking your SIM card with another phone to see if that works. 

Besides the SIM PIN your phone could also ask for a code to unlock the phone itself, or for an unlock code that's needed with carrier locked phones. 

Are you sure that you're entering the right PIN-code? Please double check this by logging into Mijn Simyo and using the PIN-code displayed under Instellingen > Simkaart. 

Can you let us know if you've managed to unlock your sim card?

Kind regards, 
Bas