my auntie found a nokia 3200 (that what it says the model is on the inside.)

it was on o2 pay as you go before but i put a 300 text messga esim card in it so she could have a new number but when i switch the phon on with the new sim card a mesage saying "Sim card registration failed".. The 300 txt sim works on my nokia 6230 and my own sim works fine on the 3200.

any ideas what is wrong wiv it?