Default Unlocked MDA Vario says wrong or incorrect sim card

Hi,

I unlocked my MDA Vario with the tool which can be found on this forum.

At first everything seemed to be OK for one or two days. It accepted my "Base-simcard" and I could use the phone-function.

Since yesterday I frequently get a message which says there is no or a wrong or sim card inserted.

When I remove the sim card, replace it and start the Vario, everything works again.

Sometimes I just have to put the wizard off and on again and it's ok again.

This happened already a few times...

Does anyone know what causes this problem?

Is it possible that the unlocking tool doesn't do the job 100% right?

Or maybe T-Mobile inserted an extra check for non-T-Mobile sim cards in the ROM part?

Best regards,

Stoffel