Problem with Nokia 3310 unlock

[chris c]

I have unlocked a Nokia 3310 which was on Virgin iemi <removed> using the code <removed>
The phone was unlocked, but will not accept a tesco sim card it just says each time Sim card not accepted.

Is there something about tesco sim cards that will not work in a Nokia 3310 phone, any help would be appreciated. I have never come accross this one before, perhaps its unique to Tesco sim cards