Received letter from bank fraud detection

island888

I received a letter from Clydesdale bank stating:

"I have been unable to contact you regarding recent activity on your Clydesdale Bank Maestro-branded debit card."

then it states: xxxxxxxxx and the last 4 digits of my card but not the same last 4 digits of the card i have now then i checked my card and realised it expired 10/10 - 17 days ago! i think my postman has lost my card? thats when i started to panic. i dont use the card at all, i just put money in it and leave it. i only got a new card sent out last october, it expires in a year? i didnt even realise it would expire so soon.

i called the number on the letter and they didnt believe who i was!!! :S i gave them all the details, my name, correct DOB, address everything! but because my mum was talking in the background she said she couldn't verify me! and now i have to wait until tomorrow to go the branch with identification. i'm really worried, i have a lot of money sitting in the bank and im racking my brain wondering if its all gone.. is that possible? what does this letter mean? what do i do?!

im not sure if i posted this in the correct section but it says banks.